[PARISC] Remove {,un}lock_kernel from perf ioctl

Remove the lock_kernel/unlock_kernel pair in the ioctl method. It
plainly wasn't protecting anything.
Signed-off-by: NMatthew Wilcox <willy@parisc-linux.org>
Signed-off-by: NKyle McMartin <kyle@parisc-linux.org>

arch/parisc/kernel/perf.c

@@ -444,7 +444,6 @@ static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	uint32_t raddr[4];
 	int error = 0;
 
-	lock_kernel();
 	switch (cmd) {
 
 	    case PA_PERF_ON:
@@ -477,8 +476,6 @@ static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
   	 		error = -ENOTTY;
 	}
 
-	unlock_kernel();
-
 	return error;
 }