Enable irq wakeups

This is needed for crust to wake us up on an incoming call.

Thanks to smaeul in #crust for the tip.

Signed-off-by: Serge Hallyn <serge@hallyn.com>

programs/sxmo_screenlock.c

@@ -76,6 +76,13 @@ configuresuspendsettingsandwakeupsources()
 		"enabled"
 	);
 
+	// Enable IRQ wakeup source
+	fprintf(stderr, "Enable irq wakeup source\n");
+	writefile(
+		"/sys/devices/platform/gpio-keys/power/wakeup",
+		"enabled"
+	 );
+
 	// Enable rtc wakeup source
 	fprintf(stderr, "Enable rtc wakeup source\n");
 	writefile(