ACPICA: Cleanup use of NEGATIVE and POSITIVE defines

ACPICA commit f88814201e01043a4f8caa69a69b799af11c44a3

These were defined in two places. Changed to ACPI_SIGN* names
and define them once in acmacros.h

This patch doesn't affect Linux kernel.

Link: https://github.com/acpica/acpica/commit/f8881420


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