efi/libstub/x86: Drop __efi_early() export and efi_config struct

efi/libstub/x86: Drop __efi_early() export and efi_config struct

The various pointers we stash in the efi_config struct which we
retrieve using __efi_early() are simply copies of the ones in
the EFI system table, which we have started accessing directly
in the previous patch. So drop all the __efi_early() related
plumbing, as well as all the assembly code dealing with efi_config,
which allows us to move the PE/COFF entry point to C code as well.

Signed-off-by: Ard Biesheuvel <[email protected]>
Cc: Arvind Sankar <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: James Morse <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>