9p: return NULL when trans not found

v9fs_match_trans function returns arbitrary transport module instead of NULL when the requested transport is not registered. This patch modifies the function to return NULL in that case.

---
commit 25ed88ed319e40fb6426e2aaefcc5f136aadd4ee
tree 281feda9127a85178d44faca59a13645d08e314d
parent 0c0b7fa3d4e80ab3e4e69b8a55661f649d1b41ff author Latchesar Ionkov <[email protected]> 1193438318 -0600 committer Latchesar Ionkov <[email protected]> 1193438318 -0600

 net/9p/mod.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

index 41d70f4..8f9763a 100644
@@ -76,9 +76,9 @@ struct p9_trans_module *v9fs_match_trans(const substring_t *name)
 	list_for_each(p, &v9fs_trans_list) {
 		t = list_entry(p, struct p9_trans_module, list);
 		if (strncmp(t->name, name->from, name->to-name->from) == 0)
-			break;
+			return t;
 	}
-	return t;
+	return NULL;
 }
 EXPORT_SYMBOL(v9fs_match_trans);