cmd: pxe_utils: Limit fdtcontroladdr usage to non-fitImage

Commit d5ba6188 ("cmd: pxe_utils: Check fdtcontroladdr in label_boot")
forces '$fdtcontroladdr' DT address as a third parameter of bootm command
even if the PXE transfer pulls in a fitImage which contains configuration
node with its own DT that is preferrable to be passed to Linux. Limit the
$fdtcontroladdr fallback utilization to non-fitImages, since it is highly
likely a fitImage would come with its own DT, while single-file images do
need a separate DT.

Fixes: d5ba6188 ("cmd: pxe_utils: Check fdtcontroladdr in label_boot")
Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Tested-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Peter Hoyes <peter.hoyes@arm.com>
Tested-by: Peter Hoyes <peter.hoyes@arm.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>

boot/pxe_utils.c

@@ -617,7 +617,7 @@ static int label_boot(struct pxe_context *ctx, struct pxe_label *label)
 	 * bootm, and adjust argc appropriately.
 	 *
 	 * Scenario 3: If there is an fdtcontroladdr specified, pass it along to
-	 * bootm, and adjust argc appropriately.
+	 * bootm, and adjust argc appropriately, unless the image type is fitImage.
 	 *
 	 * Scenario 4: fdt blob is not available.
 	 */
@@ -724,7 +724,10 @@ static int label_boot(struct pxe_context *ctx, struct pxe_label *label)
 	if (!bootm_argv[3])
 		bootm_argv[3] = env_get("fdt_addr");
 
-	if (!bootm_argv[3])
+	kernel_addr_r = genimg_get_kernel_addr(kernel_addr);
+	buf = map_sysmem(kernel_addr_r, 0);
+
+	if (!bootm_argv[3] && genimg_get_format(buf) != IMAGE_FORMAT_FIT)
 		bootm_argv[3] = env_get("fdtcontroladdr");
 
 	if (bootm_argv[3]) {
@@ -733,8 +736,6 @@ static int label_boot(struct pxe_context *ctx, struct pxe_label *label)
 		bootm_argc = 4;
 	}
 
-	kernel_addr_r = genimg_get_kernel_addr(kernel_addr);
-	buf = map_sysmem(kernel_addr_r, 0);
 	/* Try bootm for legacy and FIT format image */
 	if (genimg_get_format(buf) != IMAGE_FORMAT_INVALID &&
             IS_ENABLED(CONFIG_CMD_BOOTM))