* lib/jit_aarch64.c, lib/jit_alpha.c, lib/jit_arm.c,
	lib/jit_mips.c, lib/jit_ppc.c, lib/jit_sparc.c, lib/jit_x86.c:
	Correct wrong logic in usage of jit_live in jit_retr. The
	problem is that if a temporary is required during epilog,
	the return register might be allocated, so, jit_live must always
	be used.