hardware/libhardware: convert LOCAL_MODULE_PATH to LOCAL_MODULE_RELATIVE_PATH

LOCAL_MODULE_PATH doesn't work for multiarch builds, replace it
with LOCAL_MODULE_RELATIVE_PATH.

Change-Id: I4e4ceec61d026bbe74ba604554c06104bde42e5e
diff --git a/modules/power/Android.mk b/modules/power/Android.mk
index 50ab221..c868ded 100644
--- a/modules/power/Android.mk
+++ b/modules/power/Android.mk
@@ -17,7 +17,7 @@
 include $(CLEAR_VARS)
 
 LOCAL_MODULE := power.default
-LOCAL_MODULE_PATH := $(TARGET_OUT_SHARED_LIBRARIES)/hw
+LOCAL_MODULE_RELATIVE_PATH := hw
 LOCAL_SRC_FILES := power.c
 LOCAL_SHARED_LIBRARIES := liblog
 LOCAL_MODULE_TAGS := optional