start-sanitize-tic80

start-sanitize-tic80
	* coff-tic80.c (rtype2howto): If passed a relocation type we don't
	understand, just set the howto field to NULL, and the caller will
	print an appropriate error message.
end-sanitize-tic80
	* coffcode.h (coff_slurp_reloc_table): Pull duplicate declarations and
	code fragment out of both legs of #ifdef RELOC_PROCESSING ... #endif
	block.  Use NULL for initializations of "ptr" rather than bare 0.
	* coff-h8300.c: Fix typo in comment.
	* coff-h8500.c: Ditto.
	* coff-w65.c: Ditto
	* coff-z8k.c: Ditto.