wil6210: Fix potential memory leaks on error paths

Fix missing memory deallocation on error paths in wil_write_file_wmi()
and wil_write_file_txmgmt().

Reported-by: Ahmed Tamrawi <ahmedtamrawi@gmail.com>
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/wil6210/debugfs.c

@@ -573,8 +573,10 @@ static ssize_t wil_write_file_txmgmt(struct file *file, const char __user *buf,
 	if (!frame)
 		return -ENOMEM;
 
-	if (copy_from_user(frame, buf, len))
+	if (copy_from_user(frame, buf, len)) {
+		kfree(frame);
 		return -EIO;
+	}
 
 	params.buf = frame;
 	params.len = len;
@@ -614,8 +616,10 @@ static ssize_t wil_write_file_wmi(struct file *file, const char __user *buf,
 		return -ENOMEM;
 
 	rc = simple_write_to_buffer(wmi, len, ppos, buf, len);
-	if (rc < 0)
+	if (rc < 0) {
+		kfree(wmi);
 		return rc;
+	}
 
 	cmd = &wmi[1];
 	cmdid = le16_to_cpu(wmi->id);