ACPICA: FUNCTION_TRACE macros: Check if debug is enabled up-front.

In the functions that implement the macros, check if debug
is enabled up-front before the call to the lower debug print
function. This provides a small performance improvement.

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>