cpupower: make NLS truly optional

Loosely based on a patch for cpufrequtils, submittted by
Sergey Dryabzhinsky <sergey.dryabzhinsky@gmail.com> and

signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
diff --git a/tools/power/cpupower/Makefile b/tools/power/cpupower/Makefile
index edb021c..e8a03ac 100644
--- a/tools/power/cpupower/Makefile
+++ b/tools/power/cpupower/Makefile
@@ -137,6 +137,7 @@
 ifeq ($(strip $(NLS)),true)
 	INSTALL_NLS += install-gmo
 	COMPILE_NLS += create-gmo
+	CFLAGS += -DNLS
 endif
 
 ifeq ($(strip $(CPUFREQ_BENCH)),true)