[media] staging: lirc: Improvement in code readability

There is no need to call kfree() if memdup_user() fails, as no memory
was allocated and the error in the error-valued pointer should be returned.
Signed-off-by: NShailendra Verma <shailendra.v@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/staging/media/lirc/lirc_imon.c

@@ -408,9 +408,8 @@ static ssize_t vfd_write(struct file *file, const char __user *buf,
 
 	data_buf = memdup_user(buf, n_bytes);
 	if (IS_ERR(data_buf)) {
-		retval = PTR_ERR(data_buf);
-		data_buf = NULL;
-		goto exit;
+		mutex_unlock(&context->ctx_lock);
+		return PTR_ERR(data_buf);
 	}
 
 	memcpy(context->tx.data_buf, data_buf, n_bytes);

drivers/staging/media/lirc/lirc_sasem.c

@@ -384,9 +384,8 @@ static ssize_t vfd_write(struct file *file, const char __user *buf,
 
 	data_buf = memdup_user(buf, n_bytes);
 	if (IS_ERR(data_buf)) {
-		retval = PTR_ERR(data_buf);
-		data_buf = NULL;
-		goto exit;
+		mutex_unlock(&context->ctx_lock);
+		return PTR_ERR(data_buf);
 	}
 
 	memcpy(context->tx.data_buf, data_buf, n_bytes);