HACK: ARM: disable sleeping while atomic warning in do_signal

ARM disables interrupts in do_signal, which triggers a warning in
try_to_freeze, see details at https://lkml.org/lkml/2011/8/23/221.
To prevent the warnings, add try_to_freeze_nowarn and call it from
do_signal.

Change-Id: If7482de21c386adc705fa1ac4ecb8c7ece5bb356
Signed-off-by: Colin Cross <ccross@android.com>
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index d68d1b6..eb3a291 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -642,7 +642,7 @@
 		}
 	}
 
-	if (try_to_freeze())
+	if (try_to_freeze_nowarn())
 		goto no_signal;
 
 	/*