Adjust objcopy_test

xfails spu due to a note section getting a different vma, and some
mips targets that give section symbols a name string.  I added -p
for the executable test in an attempt to fix all the pe target fails,
but that doesn't preserve the date/time for some reason.

	* testsuite/binutils-all/objcopy.exp (objcopy_test): Move xfails
	from here to calls.  Remove "m8*-*-*" entry.  Don't xfail tic54x
	but do xfail spu, mipstx39 and mips-sgi-irix for the executable
	test.  Pass "-p" to objcopy for the executable test.