nvme-fcloop: avoid possible uninitialized variable warning

The kbuild test robot send mail of a potential use of an uninitialized
variable - "tport" in fcloop_delete_targetport() which then calls
__targetport_unreg() which uses the variable. It will never be the
case it is uninitialized as the call to __targetport_unreg() only
occurs if there is a valid nport pointer. And at the time the nport
pointer is assigned, the tport variable is set.

Remove the warning by assigning a NULL value initially.
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

drivers/nvme/target/fcloop.c

@@ -1085,7 +1085,7 @@ fcloop_delete_target_port(struct device *dev, struct device_attribute *attr,
 		const char *buf, size_t count)
 {
 	struct fcloop_nport *nport = NULL, *tmpport;
-	struct fcloop_tport *tport;
+	struct fcloop_tport *tport = NULL;
 	u64 nodename, portname;
 	unsigned long flags;
 	int ret;