frameworks/base: use proper nativehelper headers

libnativehelper exports headers under nativehelper. These were
available before incorrectly as global headers in order to give
access to jni.h.

Test: modules using frameworks/base find headers
Bug: 63762847
Change-Id: I0f9f231acdebe460f279135462f43d3e32eff64d
diff --git a/core/jni/android_hardware_location_ActivityRecognitionHardware.cpp b/core/jni/android_hardware_location_ActivityRecognitionHardware.cpp
index 44a3555..0e2b80e 100644
--- a/core/jni/android_hardware_location_ActivityRecognitionHardware.cpp
+++ b/core/jni/android_hardware_location_ActivityRecognitionHardware.cpp
@@ -17,7 +17,7 @@
 #define LOG_TAG "ActivityRecognitionHardware"
 
 #include <jni.h>
-#include <JNIHelp.h>
+#include <nativehelper/JNIHelp.h>
 
 #include <android_runtime/AndroidRuntime.h>
 #include <android_runtime/Log.h>