nvram: Drop the BKL from nvram_open()

It's safe to remove the BKL from nvram_open(): there's no open()
versus read() races: nvram_init() is very simple and race-free,
it registers the device then puts it into /proc - there's no
state init to race with.

Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <1255116426-7270-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

drivers/char/nvram.c

@@ -329,14 +329,12 @@ static int nvram_ioctl(struct inode *inode, struct file *file,
 
 static int nvram_open(struct inode *inode, struct file *file)
 {
-	lock_kernel();
 	spin_lock(&nvram_state_lock);
 
 	if ((nvram_open_cnt && (file->f_flags & O_EXCL)) ||
 	    (nvram_open_mode & NVRAM_EXCL) ||
 	    ((file->f_mode & FMODE_WRITE) && (nvram_open_mode & NVRAM_WRITE))) {
 		spin_unlock(&nvram_state_lock);
-		unlock_kernel();
 		return -EBUSY;
 	}
 
@@ -347,7 +345,6 @@ static int nvram_open(struct inode *inode, struct file *file)
 	nvram_open_cnt++;
 
 	spin_unlock(&nvram_state_lock);
-	unlock_kernel();
 
 	return 0;
 }