Replace backup file mechanism with git restore to fix restoration
bugs and simplify the build system. Files are now always restored
after build completion, ensuring a clean git state regardless of
which configuration options modify the config files.
TEST=build samsung/stumpy with iPXE for edk2 twice in a row without
failure due to dirty repo state.
Change-Id: I9c88f5ca5e5a0172f7c0a94e4edfe0192340d1e2
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/90772
Reviewed-by: Sean Rhodes <sean@starlabs.systems>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>