PM / Suspend: Do not ignore error codes returned by suspend_enter()

The current implementation of suspend-to-RAM returns 0 if there is an
error from suspend_enter(), because suspend_devices_and_enter() ignores
the return value from suspend_enter().  This patch addresses this issue
and properly keep the error return from suspend_enter() and let
suspend_devices_and_enter relay the error return.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

kernel/power/suspend.c

@@ -226,7 +226,7 @@ int suspend_devices_and_enter(suspend_state_t state)
 	if (suspend_test(TEST_DEVICES))
 		goto Recover_platform;
 
-	suspend_enter(state);
+	error = suspend_enter(state);
 
  Resume_devices:
 	suspend_test_start();