re PR target/15130 ([3.3/3.4][sh4-linux] miscompilation with -O2)

	PR target/15130
	* config/sh/sh-protos.h (sh_expand_epilogue): Change prototype.
	* config/sh/sh.c (output_stack_adjust): Take the sibcall epilogue
	into account.  Compute the correct number of general registers
	for the return value.  Generate a special push/pop sequence when
	failing to get a temporary register for non SHmedia epilogue.
	(sh_expand_epilogue): Add an argument to show whether it's for
	sibcall or not.  Set the 3rd argument of output_stack_adjust to
	-1 if needed.
	(sh_need_epilogue): Call sh_expand_epilogue with 0.
	* config/sh/sh.md (sibcall_epilogue): Call sh_expand_epilogue
	with 1.
	(epilogue): Call sh_expand_epilogue with 0.

From-SVN: r81683