leds: Add missing include for leds.h

This patch has added #include <linux/spinlock.h> to include/linux/leds.h
for rwlock_t.

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
1 file changed