soc: fsl: dpio: fix memory leak of a struct qbman on error exit path

Currently the error check for a null reg leaks a struct qbman
that was allocated earlier. Fix this by kfree'ing p on the error exit
path.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NLi Yang <leoyang.li@nxp.com>

drivers/soc/fsl/dpio/qbman-portal.c

@@ -180,6 +180,7 @@ struct qbman_swp *qbman_swp_init(const struct qbman_swp_desc *d)
 	reg = qbman_read_register(p, QBMAN_CINH_SWP_CFG);
 	if (!reg) {
 		pr_err("qbman: the portal is not enabled!\n");
+		kfree(p);
 		return NULL;
 	}