sim cris: Unbreak --disable-sim-hardware builds

With --disable-sim-hardware (--enable-sim-hardware=no),
whose default was changed to --enable-sim-hardware(=yes) in
commit 34cf51120683, building for cris-elf fails as
sim_hw_parse then doesn't exist.

A cris-elf simulator configured for --enable-sim-hardware
(or the default after to the mentioned commit) runs about
2.5x slower than one configured --disable-sim-hardware.
A further 2-5% performance regression was not investigated.

When sim_hw_parse doesn't exist, --cris-900000xx can't be
supported.  The best action here is to remove it completely,
so its absence can be identified through --help, but
avoiding littering the code with "#if WITH_HW".

sim/cris:
	* sim-if.c (cris_options) [WITH_HW]: Conditionalize
	support of option --cris-900000xx.
	(sim_open) [WITH_HW]: Conditionalize sim_hw_parse
	call.

sim/cris/sim-if.c

@@ -100,9 +100,11 @@ static const OPTION cris_options[] =
   { {"cris-naked", no_argument, NULL, OPTION_CRIS_NAKED},
      '\0', NULL, "Don't set up stack and environment",
      cris_option_handler, NULL },
+#if WITH_HW
   { {"cris-900000xx", no_argument, NULL, OPTION_CRIS_900000XXIF},
      '\0', NULL, "Define addresses at 0x900000xx with simulator semantics",
      cris_option_handler, NULL },
+#endif
   { {"cris-unknown-syscall", required_argument, NULL,
      OPTION_CRIS_UNKNOWN_SYSCALL},
      '\0', "stop|enosys|enosys-quiet", "Action at an unknown system call",
@@ -891,8 +893,14 @@ sim_open (SIM_OPEN_KIND kind, host_callback *callback, struct bfd *abfd,
 		     startmem, endmem - startmem);
 
   /* Allocate simulator I/O managed memory if none specified by user.  */
+#if WITH_HW
   if (cris_have_900000xxif)
     sim_hw_parse (sd, "/core/%s/reg %#x %i", "cris_900000xx", 0x90000000, 0x100);
+#else
+  /* With the option disabled, nothing should be able to set this variable.
+     We should "use" it, though, and why not assert that it isn't set.  */
+  ASSERT (! cris_have_900000xxif);
+#endif
 
   /* Establish any remaining configuration options.  */
   if (sim_config (sd) != SIM_RC_OK)