Do not fail EFI build with newer binutils
    
    Newer binutils versions currently trigger the following warnings due to
    a bug in gnu-efi
    
    on arm64:
    /usr/bin/ld.bfd: warning: src/boot/efi/systemd-bootaa64.elf has a LOAD segment with RWX permissions
    
    on amd64:
    /usr/bin/ld.bfd: warning: /usr/lib/crt0-efi-x86_64.o: missing .note.GNU-stack section implies executable stack
    
    This results in a build failure due to --fatal-warnings.
    Work around this issue by suppressing those warnings until gnu-efi has
    been fixed.
    
    See https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1013341
    
    (cherry picked from commit b0e5bf0451a6bc94e6e7b2a1de668b75c63f38c8)