bf561-coreb: BKL unneeded for open()

According to Mike Frysinger:

	http://permalink.gmane.org/gmane.linux.kernel/699279

open() does not need the BKL, so take it back out.

arch/blackfin/mach-bf561/coreb.c

@@ -32,7 +32,6 @@
 #include <linux/device.h>
 #include <linux/ioport.h>
 #include <linux/module.h>
-#include <linux/smp_lock.h>
 #include <linux/uaccess.h>
 #include <linux/fs.h>
 #include <asm/dma.h>
@@ -195,9 +194,9 @@ static loff_t coreb_lseek(struct file *file, loff_t offset, int origin)
 	return ret;
 }
 
+/* No BKL needed here */
 static int coreb_open(struct inode *inode, struct file *file)
 {
-	lock_kernel();
 	spin_lock_irq(&coreb_lock);
 
 	if (coreb_status & COREB_IS_OPEN)
@@ -206,12 +205,10 @@ static int coreb_open(struct inode *inode, struct file *file)
 	coreb_status |= COREB_IS_OPEN;
 
 	spin_unlock_irq(&coreb_lock);
-	unlock_kernel();
 	return 0;
 
  out_busy:
 	spin_unlock_irq(&coreb_lock);
-	unlock_kernel();
 	return -EBUSY;
 }