binutils objcopy test tidy

The main aim of this patch is to perform more objcopy tests when we
can build executables but not run them.  ie. non-native with cross
compiler available.

	* binutils-all/objcopy.exp: Delete trailing whitespace.  Use
	"string equal" rather than "string match" when making simple
	string comparisons.  Revert 2008-07-08 host_triplet checks.
	Perform non-run tests when we can build executable.
	(strip_executable, strip_executable_with_saving_a_symbol): Move
	run test later.  Take extra param on whether to perform run test.
	Update callers.
	(keep_debug_symbols_and_test_copy): Delete unused vars.