Assorted tidies

bfd/
	* elf32-microblaze.c (dbg): Delete unused variable.
	* elf32-nds32.c (relax_group_section_id_list): Make static.
	* som.c (reloc_queue): Make static.
	* xtensa-isa.c (xtisa_errno, xtisa_error_msg): Make static.
include/
	* xtensa-isa-internal.h (xtisa_errno, xtisa_error_msg): Delete.