leds: ledtrig-backlight: Fix checkpatch error

Fixes the following checkpatch error:
ERROR: space prohibited before that ':' (ctx:WxE)

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
diff --git a/drivers/leds/ledtrig-backlight.c b/drivers/leds/ledtrig-backlight.c
index c74aff1..027a2b1 100644
--- a/drivers/leds/ledtrig-backlight.c
+++ b/drivers/leds/ledtrig-backlight.c
@@ -40,7 +40,7 @@
 	int new_status = *blank ? BLANK : UNBLANK;
 
 	switch (event) {
-	case FB_EVENT_BLANK :
+	case FB_EVENT_BLANK:
 		if (new_status == n->old_status)
 			break;