arm: Bcmring: semaphore cleanup

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Leo Chen <leochen@broadcom.com>
LKML-Reference: <20100907125057.371771121@linutronix.de>