Some bright sparks have decided that a cast on a constant cannot be a
constant, so offsetof() produces this warning on clang-10:
include/intel_gnvs.h:113:1: error: static_assert expression is not an
integral constant expression
check_member(acpi_global_nvs, unused2, GNVS_CHROMEOS_ACPI_OFFSET);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/kernel.h:284:2: note: expanded from macro 'check_member'
offsetof(struct structure, member) == (offset), \
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/stddef.h:20:32: note: expanded from macro 'offsetof'
^
include/intel_gnvs.h:113:1: note: cast that performs the conversions of
a reinterpret_cast is ot allowed in a constant expression
include/linux/stddef.h:20:33: note: expanded from macro 'offsetof'
Fix it by using the compiler built-in version, if available. This syncs
the function to the same implementation as Linux v5.16 in this header
file.
Signed-off-by: Simon Glass <sjg@chromium.org>
