Allow user names longer than 32 bytes

We artificially limited the user name to 32 bytes, but modern servers handle
larger.  Set the maximum length to a reasonable 256, and make the user name
string dynamically allocated rather than a fixed size in session structure.
Also clean up old checkpatch warning.

Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index 2a930a7..7228179 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -100,6 +100,7 @@
 		memset(buf_to_free->password, 0, strlen(buf_to_free->password));
 		kfree(buf_to_free->password);
 	}
+	kfree(buf_to_free->user_name);
 	kfree(buf_to_free->domainName);
 	kfree(buf_to_free);
 }