lavc: Add flag to allow profile mismatch with hardware decoding

(cherry picked from commit 64a5260c)

doc/APIchanges

@@ -15,6 +15,9 @@ libavutil:     2015-08-28
 
 API changes, most recent first:
 
+2017-06-14 - xxxxxxx - lavc 57.99.100 - avcodec.h
+  Add AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH.
+
 2017-06-14 - xxxxxxx - lavu 55.65.100 - hwcontext.h
   Add AV_HWDEVICE_TYPE_NONE, av_hwdevice_find_type_by_name(),
   av_hwdevice_get_type_name() and av_hwdevice_iterate_types().

libavcodec/avcodec.h

@@ -4001,6 +4001,20 @@ typedef struct AVHWAccel {
  */
 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
 
+/**
+ * Hardware acceleration should still be attempted for decoding when the
+ * codec profile does not match the reported capabilities of the hardware.
+ *
+ * For example, this can be used to try to decode baseline profile H.264
+ * streams in hardware - it will often succeed, because many streams marked
+ * as baseline profile actually conform to constrained baseline profile.
+ *
+ * @warning If the stream is actually not supported then the behaviour is
+ *          undefined, and may include returning entirely incorrect output
+ *          while indicating success.
+ */
+#define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
+
 /**
  * @}
  */

libavcodec/version.h

@@ -28,7 +28,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVCODEC_VERSION_MAJOR  57
-#define LIBAVCODEC_VERSION_MINOR  98
+#define LIBAVCODEC_VERSION_MINOR  99
 #define LIBAVCODEC_VERSION_MICRO 100
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \