efi: Remove the declaration of efi_late_init() as the function is unused

efi: Remove the declaration of efi_late_init() as the function is unused

The following commit:

  7b0a911478c74 ("efi/x86: Move the EFI BGRT init code to early init code")

... removed the implementation and all the references to
efi_late_init() but the function is still declared at
include/linux/efi.h.

Hence, remove the unnecessary declaration.

Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180711094040.12506-6-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>