use xstrdup and friends more

use xstrdup and friends more

gas/ChangeLog:

2016-03-29  Trevor Saunders  <tbsaunde+binutils@tbsaunde.org>

	* config/tc-hppa.c (pa_space): Use xstrdup where appropriate.
	(pa_subspace): Likewise.
	(create_new_space): Likewise.
	(create_new_subspace): Likewise.
	* config/tc-mips.c (mips_lookup_insn): Likewise.
	* config/tc-tic4x.c (tic4x_asg): Likewise.
	* config/tc-tic54x.c (tic54x_eval): Likewise.
	(stag_add_field): Likewise.
	(tic54x_usect): Likewise.
	(tic54x_clink): Likewise.
	(tic54x_set_default_include): Likewise.
	(tic54x_include): Likewise.
	(tic54x_message): Likewise.
	(tic54x_sblock): Likewise.
	(tic54x_var): Likewise.
	(subsym_ismember): Likewise.
	(subsym_substitute): Likewise.
	* config/tc-xtensa.c (xg_replace_opname): Likewise.
	(xg_translate_sysreg_op): Likewise.
	(xg_translate_idioms): Likewise.
	(md_assemble): Likewise.
	(cache_literal_section): Likewise.