efi/libstub/x86: Fix unused-variable warning

The only users of these got removed, so they also need to be
removed to avoid warnings:

  arch/x86/boot/compressed/eboot.c: In function 'setup_efi_pci':
  arch/x86/boot/compressed/eboot.c:117:16: error: unused variable 'nr_pci' [-Werror=unused-variable]
    unsigned long nr_pci;
                  ^~~~~~
  arch/x86/boot/compressed/eboot.c: In function 'setup_uga':
  arch/x86/boot/compressed/eboot.c:244:16: error: unused variable 'nr_ugas' [-Werror=unused-variable]
    unsigned long nr_ugas;
                  ^~~~~~~

Fixes: 2732ea0d

 ("efi/libstub: Use a helper to iterate over a EFI handle array")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200113172245.27925-4-ardb@kernel.org