x86/efi: Log 32/64-bit mismatch with kernel as an error

Log the message

    No EFI runtime due to 32/64-bit mismatch with kernel

as an error condition, as several things like efivarfs won’t work
without the EFI runtime.

Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>