hw/ppc/sam460ex: Update u-boot-sam460ex

Update the sam460ex firmware to match 2015.c version from the machine
vendor which fixes USB devices and some other bugs. Also cherry pick
some commits from upstream U-Boot that moves licenses in a subdir and
allows gitlab to correctly detect and show license information. Drop
version number from the binary name to avoid needing to change it in
case of future updates.

Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Message-Id: <20251028151923.10DBB5972E5@zero.eik.bme.hu>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>

pc-bios/meson.build

@@ -74,7 +74,7 @@ blobs = [
   'pnv-pnor.bin',
   'palcode-clipper',
   'u-boot.e500',
-  'u-boot-sam460-20100605.bin',
+  'u-boot-sam460.bin',
   'qemu_vga.ndrv',
   'edk2-licenses.txt',
   'hppa-firmware.img',