Merge commit '142e76f1'

* commit '142e76f1':
  swscale: fix crash with dithering due incorrect offset calculation.
  matroskadec: fix stupid typo (!= -> ==)
  build: remove duplicates from order-only directory prerequisite list
  build: rework rules for things in the tools dir
  configure: fix --cpu=host with gcc 4.6
  ARM: use const macro to define constant data in asm
  bitdepth: simplify FUNC/FUNCC macros
  dsputil: remove ff_emulated_edge_mc macro used in one place
  9/10-bit: simplify clipping macros
  matroskadec: reindent
  matroskadec: defer parsing of cues element until we seek.
  lavc: add support for codec-specific defaults.
  lavc: make avcodec_alloc_context3 officially public.
  lavc: remove a half-working attempt at different defaults for audio/video codecs.
  ac3dec: add a drc_scale private option
  lavf: add avformat_find_stream_info()
  lavc: introduce avcodec_open2() as a replacement for avcodec_open().

Conflicts:
	Makefile
	libavcodec/utils.c
	libavformat/avformat.h
	libswscale/swscale_internal.h

Merged-by: Michael Niedermayer <michaelni@gmx.at>