Merge patch series "Select CONFIG_64BIT for sandbox64 and x86_64"

Andrew Goodbody <andrew.goodbody@linaro.org> says:

Picking up a series from Dan Carpenter and applying requested
changes for v2.

I had previously set CONFIG_64BIT for arm64.  This patchset does the
same thing for sandbox and x86_64.  (Mips and riscv were already
doing it).  This CONFIG option is used in the Makefile to determine
if it's a 32 or 64 bit system for the CHECKER.

Makefile
  1052  # the checker needs the correct machine size
  1053  CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)

Link: https://lore.kernel.org/r/20241216180736.1933807-1-andrew.goodbody@linaro.org