Revert "libsensors: Fix build breakage. Don't build IIO hal unless requested"

Does not fix it.
Will also be reverting the iio hal until I understand the dependencies.

This reverts commit a779188720ba7d7915bde21b18d89bc7bb6e6ebf.
diff --git a/libsensors/Android.mk b/libsensors/Android.mk
index 2b704db..f6c9323 100644
--- a/libsensors/Android.mk
+++ b/libsensors/Android.mk
@@ -16,7 +16,6 @@
 LOCAL_PATH := $(call my-dir)
 
 ifneq ($(TARGET_SIMULATOR),true)
-ifeq ($(BUILD_INVENSENSE_IIO_HAL), true)
 
 # InvenSense fragment of the HAL
 include $(CLEAR_VARS)
@@ -142,5 +141,4 @@
 OVERRIDE_BUILT_MODULE_PATH := $(TARGET_OUT_INTERMEDIATE_LIBRARIES)
 include $(BUILD_PREBUILT)
 
-endif # BUILD_INVENSENSE_IIO_HAL
 endif # !TARGET_SIMULATOR