avcodec: Add the extended pixel format profile for HEVC

It is supported by the NVIDIA video SDK 7.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

doc/APIchanges

@@ -13,6 +13,9 @@ libavutil:     2015-08-28
 
 API changes, most recent first:
 
+2016-xx-xx - xxxxxxx - lavc 59.27.0 - avcodec.h
+  Add FF_PROFILE_HEVC_REXT, the extended pixel format profile for HEVC.
+
 2016-08-24 - xxxxxxx - lavu 55.21.0 - imgutils.h
   Add av_image_copy_uc_from(), a version of av_image_copy() for copying
   from GPU mapped memory.

libavcodec/avcodec.h

@@ -2961,6 +2961,7 @@ typedef struct AVCodecContext {
 #define FF_PROFILE_HEVC_MAIN                        1
 #define FF_PROFILE_HEVC_MAIN_10                     2
 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE          3
+#define FF_PROFILE_HEVC_REXT                        4
 
     /**
      * level

libavcodec/version.h

@@ -28,7 +28,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVCODEC_VERSION_MAJOR 57
-#define LIBAVCODEC_VERSION_MINOR 26
+#define LIBAVCODEC_VERSION_MINOR 27
 #define LIBAVCODEC_VERSION_MICRO  0
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \