firmware/google: drop 'select EFI' to avoid recursive dependency

The GOOGLE_SMI Kconfig symbol depends on DMI and selects EFI.  This
causes problems on other archs when introducing DMI support that depends
on EFI, as it results in a recursive dependency:

  arch/arm/Kconfig:1845:error: recursive dependency detected!
  arch/arm/Kconfig:1845:	symbol DMI depends on EFI

Fix by changing the 'select EFI' to a 'depends on EFI'.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: David Rientjes <rientjes@google.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>