audioconvert: define unique strings for AV_CH_LAYOUT_5POINT{0,1}_BACK

Previously the string for AV_CH_LAYOUT_5POINT{0,1}_BACK was the same
of the string for AV_CH_LAYOUT_5POINT{0,1}.

This is required for discerning the two channel layouts, given a
channel layout string.

libavutil/audioconvert.c

@@ -52,9 +52,9 @@ static const struct {
     { "4.0",         4,  AV_CH_LAYOUT_4POINT0 },
     { "quad",        4,  AV_CH_LAYOUT_QUAD },
     { "5.0",         5,  AV_CH_LAYOUT_5POINT0 },
-    { "5.0",         5,  AV_CH_LAYOUT_5POINT0_BACK },
+    { "5.0(back)",   5,  AV_CH_LAYOUT_5POINT0_BACK },
     { "5.1",         6,  AV_CH_LAYOUT_5POINT1 },
-    { "5.1",         6,  AV_CH_LAYOUT_5POINT1_BACK },
+    { "5.1(back)",   6,  AV_CH_LAYOUT_5POINT1_BACK },
     { "5.1+downmix", 8,  AV_CH_LAYOUT_5POINT1|AV_CH_LAYOUT_STEREO_DOWNMIX, },
     { "7.1",         8,  AV_CH_LAYOUT_7POINT1 },
     { "7.1(wide)",   8,  AV_CH_LAYOUT_7POINT1_WIDE },

libavutil/avutil.h

@@ -41,7 +41,7 @@
 
 #define LIBAVUTIL_VERSION_MAJOR 51
 #define LIBAVUTIL_VERSION_MINOR 11
-#define LIBAVUTIL_VERSION_MICRO  0
+#define LIBAVUTIL_VERSION_MICRO  1
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
                                                LIBAVUTIL_VERSION_MINOR, \