* config/mmix/mmix-protos.h: Convert prototypes to ISO C90.

	* config/mmix/mmix.c: Convert functions to ISO C90.
  	(mmix_eh_return_handler_rtx, mmix_output_shifted_value): Tweak
	formatting.
	(mmix_get_hard_reg_initial_val): Tweak section head comment.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@69466 138bc75d-0d04-0410-961f-82ee72b054a4