Michael Brown
de37652044
[efi] Prevent EFI code from being linked in to non-EFI builds
Ensure that efi_systab is an undefined symbol in non-EFI builds. In
particular, this prevents users from incorrectly enabling IMAGE_EFI in
a BIOS build of iPXE.
Signed-off-by: Michael Brown <mcb30@ipxe.org>