Detect SSE2 support

Compilation on an older 32-bit Athlon XP chip fails with the error
"./Utils/AEUtil.h:50:12: error: '__m128i' does not name a type"
This is because the __m128i type is only available on SSE2 platforms.
Modify the preprocessor logic to detect SSE and SSE2 support separately.

The "emmintrin.h" header should only be included on SSE2 platforms as
well.
Merge pull request #2612 from Jose123456/master

[AE] Fix for non-SSE2 platforms.
DVDAudioCodecLPcm: Do not use AVCODEC_MAX_AUDIO_FRAME_SIZE which has been removed from FFmpeg 2.0 and dynamically allocate buffers as needed.
DVDAudioCodecPcm: Do not use AVCODEC_MAX_AUDIO_FRAME_SIZE since it is gone in FFmpeg 2.0 and dynamically allocate buffers as needed.
DVDAudioCodec(L)Pcm: Disable copying of the class.
Merge pull request #3006 from aballier/ffmpeg2

Stop using AVCODEC_MAX_AUDIO_FRAME_SIZE in (L)Pcm decoders.