[Android] Recompiled extlibs/ properly

External libraries are compiled with the latest NDK version (r9) with android-9 as API level using the recommended flags (see docs/).
External libraries are now compiled without the so version suffix because the NDK strips it at install time.
Static libraries of libsndfile and OpenAL-Soft have been removed because of their non-permissive license. It now uses their shared libraries.

NOTE: The audio module is disabled on MIPS arches because I was unable to compile OpenAL-Soft. Once the compilation issue fixed, I'll re-enable it.

extlibs/android/extlibs/Android.mk

@@ -14,40 +14,50 @@ include $(PREBUILT_STATIC_LIBRARY)
 
 include $(CLEAR_VARS)
 LOCAL_MODULE := ogg
-LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libogg.a
+LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libogg.so
 LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
+TARGET_ARCH_ABI := armeabi armeabi-v7a x86
 
-include $(PREBUILT_STATIC_LIBRARY)
-
-include $(CLEAR_VARS)
-LOCAL_MODULE := vorbis
-LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libvorbis.a
-LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
-
-include $(PREBUILT_STATIC_LIBRARY)
-
-include $(CLEAR_VARS)
-LOCAL_MODULE := vorbisenc
-LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libvorbisenc.a
-LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
-
-include $(PREBUILT_STATIC_LIBRARY)
+include $(PREBUILT_SHARED_LIBRARY)
 
 include $(CLEAR_VARS)
 LOCAL_MODULE := flac
-LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libFLAC.a
+LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libFLAC.so
 LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
+TARGET_ARCH_ABI := armeabi armeabi-v7a x86
 
-include $(PREBUILT_STATIC_LIBRARY)
+include $(PREBUILT_SHARED_LIBRARY)
+
+include $(CLEAR_VARS)
+LOCAL_MODULE := vorbis
+LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libvorbis.so
+LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
+TARGET_ARCH_ABI := armeabi armeabi-v7a x86
+
+include $(PREBUILT_SHARED_LIBRARY)
+
+include $(CLEAR_VARS)
+LOCAL_MODULE := vorbisenc
+LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libvorbisenc.so
+LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
+TARGET_ARCH_ABI := armeabi armeabi-v7a x86
+
+include $(PREBUILT_SHARED_LIBRARY)
 
 include $(CLEAR_VARS)
 LOCAL_MODULE := sndfile
-LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libsndfile.a
+LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libsndfile.so
 LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
-include $(PREBUILT_STATIC_LIBRARY)
+LOCAL_SHARED_LIBRARIES := ogg flac vorbis vorbisenc
+TARGET_ARCH_ABI := armeabi armeabi-v7a x86
+
+include $(PREBUILT_SHARED_LIBRARY)
 
 include $(CLEAR_VARS)
 LOCAL_MODULE := openal
-LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libopenal.a
+LOCAL_SRC_FILES := lib/$(TARGET_ARCH_ABI)/libopenal.so
 LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
-include $(PREBUILT_STATIC_LIBRARY)
+LOCAL_SHARED_LIBRARIES := ogg flac vorbis vorbisenc
+TARGET_ARCH_ABI := armeabi armeabi-v7a x86
+
+include $(PREBUILT_SHARED_LIBRARY)