ext4: remove redundant assignment of variable ex

Variable ex is assigned a variable that is not being read, the assignment
is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20201021132326.148052-1-colin.king@canonical.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/extents.c

@@ -5988,7 +5988,6 @@ int ext4_ext_replay_set_iblocks(struct inode *inode)
 			kfree(path);
 			break;
 		}
-		ex = path2[path2->p_depth].p_ext;
 		for (i = 0; i <= max(path->p_depth, path2->p_depth); i++) {
 			cmp1 = cmp2 = 0;
 			if (i <= path->p_depth)