generate_signed_fit_image: Align FIT image to 64-byte boundary

Currently, external data is used for the FIT image so it can be aligned
properly matching the kernel expectation for the fdt to be 8 bytes
(64 bits) aligned.

FSL CAAM crypt module uses DMA, which expects images to be 64 byte
aligned. Let's use this alignment so the FIT image matches all the
requirements.

Signed-off-by: Ariel D'Alessandro <ariel.dalessandro@collabora.com>

scripts/generate_signed_fit_image.py

@@ -56,10 +56,12 @@ def fit_image_create(kernel, ramdisk, dtb, fit_template, fitimage):
         ivt.flush()
 
         print("Generating FIT image:")
-        # Use external data for the fit image at least aligned at 8 bytes (64)
-        # bits to match the expectation of the kernel (fdt to be 64 bit
-        # aligned) when using fdt in place.
-        subprocess.run(["mkimage", "-E", "-B", "0x8", "-f", ivt.name, fitimage], check=True)
+        # Use external data for the FIT image so it can be aligned properly
+        # matching the following requirements:
+        # - Kernel expects fdt to be 8 bytes (64 bits) aligned.
+        # - FSL CAAM crypt module uses DMA, which expects images to be 64 byte
+        #   aligned.
+        subprocess.run(["mkimage", "-E", "-B", "0x40", "-f", ivt.name, fitimage], check=True)
 
 # Sign the whole image with assumption it is loaded at FIT_LOADADDR
 def sign_image(image, csf_template, length):