drivers/leds: Add export.h for THIS_MODULE to leds-cobalt-raq.c

In preparation of the module.h usage cleanup, call out the export.h
to avoid build failures when that happens.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/leds/leds-cobalt-raq.c b/drivers/leds/leds-cobalt-raq.c
index 438d483..aac1c07 100644
--- a/drivers/leds/leds-cobalt-raq.c
+++ b/drivers/leds/leds-cobalt-raq.c
@@ -24,6 +24,7 @@
 #include <linux/platform_device.h>
 #include <linux/spinlock.h>
 #include <linux/types.h>
+#include <linux/export.h>
 
 #define LED_WEB		0x04
 #define LED_POWER_OFF	0x08