Refactor android jni makefiles

jni/Android.mk

 LOCAL_PATH := $(call my-dir)
 
-include $(CLEAR_VARS)
-
-LOCAL_MODULE    := libretro
-LOCAL_CFLAGS :=
-
-ifeq ($(TARGET_ARCH),arm)
-LOCAL_CPPFLAGS += -DANDROID_ARM
-endif
+CORE_DIR := $(LOCAL_PATH)/..
 
-ifeq ($(TARGET_ARCH),x86)
-LOCAL_CPPFLAGS +=  -DANDROID_X86
-endif
-
-ifeq ($(TARGET_ARCH),mips)
-LOCAL_CPPFLAGS += -DANDROID_MIPS -D__mips__ -D__MIPSEL__
-endif
-
-LOCAL_SRC_FILES = ../audio.cpp ../cpu.cpp ../vmu.cpp ../main.cpp ../video.cpp ../t0.cpp ../t1.cpp ../basetimer.cpp ../bitwisemath.cpp ../flashfile.cpp ../flash.cpp ../rom.cpp ../ram.cpp ../interrupts.cpp
-LOCAL_CPPFLAGS += -O3 -std=c++98 -ffast-math -funroll-loops
+SOURCES_CPP := $(wildcard $(CORE_DIR)/*.cpp)
 
+COREFLAGS := -ffast-math -funroll-loops
 
+include $(CLEAR_VARS)
+LOCAL_MODULE    := retro
+LOCAL_SRC_FILES := $(SOURCES_CPP)
+LOCAL_CPPFLAGS  := -std=c++98 $(COREFLAGS)
+LOCAL_LDFLAGS   := -Wl,-version-script=$(CORE_DIR)/link.T
 include $(BUILD_SHARED_LIBRARY)

jni/Application.mk

 APP_ABI := all
-APP_STL := stlport_static
+APP_STL := gnustl_static