soc: fsl/qe: Use of_get_child_by_name helper

Use the of_get_child_by_name() helper instead of open coding searching
for the 'firmware' child node. This removes directly accessing the name
pointer as well.

Cc: Qiang Zhao <qiang.zhao@nxp.com>
Cc: Li Yang <leoyang.li@nxp.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Qiang Zhao <qiang.zhao@nxp.com>
Signed-off-by: Li Yang <leoyang.li@nxp.com>

drivers/soc/fsl/qe/qe.c

@@ -588,11 +588,7 @@ struct qe_firmware_info *qe_get_firmware_info(void)
 	}
 
 	/* Find the 'firmware' child node */
-	for_each_child_of_node(qe, fw) {
-		if (strcmp(fw->name, "firmware") == 0)
-			break;
-	}
-
+	fw = of_get_child_by_name(qe, "firmware");
 	of_node_put(qe);
 
 	/* Did we find the 'firmware' node? */