Merge remote-tracking branch 'qatar/master'

* qatar/master:
  swscale: try to use mmap only if available
  configure: check for mprotect
  wmapro: use planar sample format
  wmalossless: output in planar sample format
  wmadec: use float planar sample format output
  shorten: use planar sample format
  lavc: update documentation for AVFrame.extended_data

Conflicts:
	libavcodec/shorten.c

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

libavcodec/avcodec.h

@@ -1066,7 +1066,7 @@ typedef struct AVFrame {
      * extended_data must be used by the decoder in order to access all
      * channels.
      *
-     * encoding: unused
+     * encoding: set by user
      * decoding: set by AVCodecContext.get_buffer()
      */
     uint8_t **extended_data;