hw_random: Remove BKL from core

hw_random core is completely serialized with rng_mutex. No need for
the cycle_kernel_lock() magic.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <20091010153349.844488872@linutronix.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/core.c

@@ -87,7 +87,6 @@ static int rng_dev_open(struct inode *inode, struct file *filp)
 		return -EINVAL;
 	if (filp->f_mode & FMODE_WRITE)
 		return -EINVAL;
-	cycle_kernel_lock();
 	return 0;
 }