ACPICA: MSVC6: Fix build issue for variable argument macros

ACPICA commit 72f5a358f28c5d154ed613c142c7dca03192c5ee

This patch intoduces generic variable macro detection support and fixes
build breakage issue with macros using __VA_ARGS__ feature defined in
C99.

This patch fixes this build issue. Lv Zheng.

This patch doesn't affect Linux kernel.

Link: https://github.com/acpica/acpica/commit/72f5a358


Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>