Fix missing files for ld when test suite not compiled in the source directory

This patch fixes an issues with six test suite expect files that do not
run correctly when the test suite is not built in the source directory.  The
issue is these tests are not using the current "standard_testfile" call
but rather using the older set command to initialize the "testfile",
"srcfile" and "binprefix" variables or are missing the set for the
"binprefix" variable.

-----------------------------------------------

gdb/testsuite/ChangeLog

2016-08-19  Carl Love  <cel@us.ibm.com>

	* gdb.arch/altivec-regs.exp: Use standard_testfile instead of
	maintaining separate logic for constructing the output path.
	* gdb.arch/powerpc-d128-regs.exp: Likewise.
	* gdb.arch/ppc-dfp.exp: Likewise.
	* gdb.arch/ppc-fp.exp: Likewise.
	* gdb.arch/vsx-regs.exp: Likewise.
	* gdb.arch/altivec-abi.exp: Likewise, plus added local variable
	binprefix for generating the additional binary files.

gdb/testsuite/ChangeLog

@@ -1,3 +1,14 @@
+2016-08-19  Carl Love  <cel@us.ibm.com>
+
+	* gdb.arch/altivec-regs.exp: Use standard_testfile instead of
+	maintaining separate logic for constructing the output path.
+	* gdb.arch/powerpc-d128-regs.exp: Likewise.
+	* gdb.arch/ppc-dfp.exp: Likewise.
+	* gdb.arch/ppc-fp.exp: Likewise.
+	* gdb.arch/vsx-regs.exp: Likewise.
+	* gdb.arch/altivec-abi.exp: Likewise, plus added local variable
+	binprefix for generating the additional binary files.
+
 2016-08-19  Pedro Alves  <palves@redhat.com>
 
 	* gdb.trace/mi-trace-frame-collected.exp

gdb/testsuite/gdb.arch/altivec-abi.exp

@@ -26,9 +26,7 @@ if {![istarget "powerpc*"] || [skip_altivec_tests]} then {
     return
 }
 
-set testfile "altivec-abi"
+standard_testfile
-set binfile ${objdir}/${subdir}/${testfile}
-set srcfile ${testfile}.c
 
 if [get_compiler_info] {
     warning "get_compiler failed"
@@ -146,6 +144,8 @@ proc altivec_abi_tests { extra_flags force_abi } {
 }
 
 if [test_compiler_info gcc*] {
+    set binprefix ${binfile}
+
     with_test_prefix "default ABI, auto" {
 	altivec_abi_tests  "additional_flags=-maltivec" "auto"
     }
@@ -156,23 +156,23 @@ if [test_compiler_info gcc*] {
 	# On 64-bit GNU/Linux with GCC 4.1 and 4.2, -mabi=no-altivec
 	# was broken, so skip those tests there.
 	if { ![is_lp64_target] || ![test_compiler_info "gcc-4-\[12\]-*"] } {
-	    set binfile ${objdir}/${subdir}/${testfile}-ge-ge
+	    set binfile ${binprefix}-ge-ge
 	    with_test_prefix "generic ABI, forced" {
 		altivec_abi_tests "additional_flags=-maltivec additional_flags=-mabi=no-altivec" "generic"
 	    }
 
-	    set binfile ${objdir}/${subdir}/${testfile}-ge-auto
+	    set binfile ${binprefix}-ge-auto
 	    with_test_prefix "generic ABI, auto" {
 		altivec_abi_tests "additional_flags=-maltivec additional_flags=-mabi=no-altivec" "auto"
 	    }
 	}
 
-	set binfile ${objdir}/${subdir}/${testfile}-av-av
+	set binfile ${binprefix}-av-av
 	with_test_prefix "AltiVec ABI, forced" {
 	    altivec_abi_tests "additional_flags=-maltivec additional_flags=-mabi=altivec" "altivec"
 	}
 
-	set binfile ${objdir}/${subdir}/${testfile}-av-auto
+	set binfile ${binprefix}-av-auto
 	with_test_prefix "AltiVec ABI, auto" {
 	    altivec_abi_tests "additional_flags=-maltivec additional_flags=-mabi=altivec" "auto"
 	}

gdb/testsuite/gdb.arch/altivec-regs.exp

@@ -27,9 +27,7 @@ if {![istarget "powerpc*"] || [skip_altivec_tests]} then {
     return
 }
 
-set testfile "altivec-regs"
+standard_testfile
-set binfile ${objdir}/${subdir}/${testfile}
-set srcfile ${testfile}.c
 
 set compile_flags {debug nowarnings}
 if [get_compiler_info] {

gdb/testsuite/gdb.arch/powerpc-d128-regs.exp

@@ -25,9 +25,7 @@ if ![istarget "powerpc64*-*"] then {
     return
 }
 
-set testfile "powerpc-d128-regs"
+standard_testfile
-set srcfile ${testfile}.c
-set binfile ${objdir}/${subdir}/${testfile}
 
 if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {quiet debug}] != "" } {
      untested powerpc-d128-regs.exp

gdb/testsuite/gdb.arch/ppc-dfp.exp

@@ -21,9 +21,7 @@ if ![istarget "powerpc*"] then {
     return
 }
 
-set testfile "ppc-dfp"
+standard_testfile
-set binfile ${objdir}/${subdir}/${testfile}
-set srcfile ${testfile}.c
 
 if [get_compiler_info] {
     warning "get_compiler failed"

gdb/testsuite/gdb.arch/ppc-fp.exp

@@ -21,9 +21,7 @@ if ![istarget "powerpc*"] then {
     return
 }
 
-set testfile "ppc-fp"
+standard_testfile
-set binfile ${objdir}/${subdir}/${testfile}
-set srcfile ${testfile}.c
 
 if [get_compiler_info] {
     warning "get_compiler failed"

gdb/testsuite/gdb.arch/vsx-regs.exp

@@ -24,9 +24,7 @@ if {![istarget "powerpc*"] || [skip_vsx_tests]} then {
     return
 }
 
-set testfile "vsx-regs"
+standard_testfile
-set binfile ${objdir}/${subdir}/${testfile}
-set srcfile ${testfile}.c
 
 set compile_flags {debug nowarnings quiet}
 if [get_compiler_info] {