testsuite: print any leaking torture options for debugging

This was helpful when debugging the recent multilib testsuite failure.

gcc/testsuite:
	* lib/torture-options.exp: print the value of non-empty options:
	torture_without_loops, torture_with_loops, LTO_TORTURE_OPTIONS.

Signed-off-by: Vineet Gupta <vineetg@rivosinc.com>