* mdebugread.c (parse_procedure): Remove _sigtramp kludges for

	* mdebugread.c (parse_procedure):  Remove _sigtramp kludges for
	alpha and irix. The _sigtramp case has to be handled properly
	in the tdep files if we have no ecoff debugging info.
	* alpha-tdep.c (alpha_frame_saved_pc, alpha_frame_chain),
	mips-tdep.c (mips_frame_saved_pc):  Handle signal handler frames
	without PC_REGNUM kludge.
	* mdebugread.c (fixup_sigtramp), mips-tdep.c (read_next_frame_reg):
	Clean up handling of mips sigtramp frames, improve comments.