Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
* gdb.base/charset-malloc.c: New file.
* gdb.base/charset.c (malloc_stub): New prototype.
(main): Call it instead of malloc itself.
* gdb.base/charset.exp: Use only prepare_for_testing.
(binfile): Remove the variable.