Revert "Revert GRUB2 patch causing boot failure on some old x86_64 BI…

…OSes (#3324)"

This reverts commit 478538e.

For HAOS release 13.0 the patch that diverges our GRUB build from upstream to
fix boot on some old Atom boards should be reverted. While this patch fixed
issues on some boards, it significantly changes how the kernel is loaded with
GRUB 2.12 and causes issues on other, more recent devices. There's a call to
action for users of those old boards in #3305 to gather information which
should result in upstream patch targeted specifically to the boards affected
[1].

Fixes #3348

[1] https://lists.gnu.org/archive/html/grub-devel/2024-07/msg00009.html

buildroot-external/configs/generic_x86_64_defconfig

@@ -4,7 +4,7 @@ BR2_DL_DIR="/cache/dl"
 BR2_CCACHE=y
 BR2_CCACHE_DIR="/cache/cc"
 BR2_ENABLE_LTO=y
-BR2_GLOBAL_PATCH_DIR="$(BR2_EXTERNAL_HASSOS_PATH)/patches $(BR2_EXTERNAL_HASSOS_PATH)/board/pc/patches $(BR2_EXTERNAL_HASSOS_PATH)/board/pc/generic-x86-64/patches"
+BR2_GLOBAL_PATCH_DIR="$(BR2_EXTERNAL_HASSOS_PATH)/patches $(BR2_EXTERNAL_HASSOS_PATH)/board/pc/patches"
 BR2_SSP_REGULAR=y
 BR2_TARGET_GENERIC_HOSTNAME="homeassistant"
 BR2_TARGET_GENERIC_ISSUE="Welcome to Home Assistant"