treewide: Drop image_header_t typedef

This is not needed and we should avoid typedefs. Use the struct instead
and rename it to indicate that it really is a legacy struct.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/fpga/socfpga_arria10.c b/drivers/fpga/socfpga_arria10.c
index e86e3b7..3b785e6 100644
--- a/drivers/fpga/socfpga_arria10.c
+++ b/drivers/fpga/socfpga_arria10.c
@@ -555,14 +555,14 @@
 	/* Load image header into buffer */
 	ret = request_firmware_into_buf(dev,
 					fpga_loadfs->fpga_fsinfo->filename,
-					buffer_p, sizeof(struct image_header),
+					buffer_p, sizeof(struct legacy_img_hdr),
 					0);
 	if (ret < 0) {
 		debug("FPGA: Failed to read image header from flash.\n");
 		return -ENOENT;
 	}
 
-	if (image_get_magic((struct image_header *)buffer_p) != FDT_MAGIC) {
+	if (image_get_magic((struct legacy_img_hdr *)buffer_p) != FDT_MAGIC) {
 		debug("FPGA: No FDT magic was found.\n");
 		return -EBADF;
 	}
diff --git a/drivers/usb/gadget/f_sdp.c b/drivers/usb/gadget/f_sdp.c
index 74548ab..af4b167 100644
--- a/drivers/usb/gadget/f_sdp.c
+++ b/drivers/usb/gadget/f_sdp.c
@@ -835,7 +835,7 @@
 
 			printf("Found header at 0x%08x\n", sdp_func->jmp_address);
 
-			image_header_t *header =
+			struct legacy_img_hdr *header =
 				sdp_ptr(sdp_func->jmp_address);
 #ifdef CONFIG_SPL_LOAD_FIT
 			if (image_get_magic(header) == FDT_MAGIC) {