boot/edk2: bump to version edk2-stable202508

For release notes since edk2-stable202505, see:
https://github.com/tianocore/edk2/releases/tag/edk2-stable202508

This commit also updates the edk2-platforms packages with the last
commit merged at the edk2 release date (2025-08-12), which corresponds
to commit [1].
The edk2-non-osi package is not updated because it did not received
any commit since the last edk2 bump.

This commit has been runtime tested with tests using EDK2 package,
with commands:

    support/testing/run-tests \
        -d dl -o output_folder \
            tests.boot.test_edk2 \
            tests.boot.test_grub.TestGrubAArch64EFI \
            tests.boot.test_grub.TestGrubi386EFI \
            tests.boot.test_grub.TestGrubRiscV64EFI \
            tests.boot.test_grub.TestGrubX8664EFI \
            tests.fs.test_iso9660.TestIso9660Grub2EFI \
            tests.fs.test_iso9660.TestIso9660Grub2Hybrid \
            tests.package.test_fwts

It has also been runtime tested (by booting in qemu) with defconfigs
using EDK2 package:
qemu_aarch64_sbsa_defconfig
qemu_loongarch64_virt_efi_defconfig
qemu_riscv64_virt_efi_defconfig

[1] d1b297b2aa

Cc: Dick Olsson <hi@senzilla.io>
Cc: Romain Naour <romain.naour@smile.fr>
Cc: Vincent Stehlé <vincent.stehle@arm.com>
Tested-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

boot/edk2/edk2.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-EDK2_VERSION = edk2-stable202505
+EDK2_VERSION = edk2-stable202508
 EDK2_SITE = https://github.com/tianocore/edk2
 EDK2_SITE_METHOD = git
 EDK2_LICENSE = BSD-2-Clause-Patent