lavfi/transpose: restore validity of values in range 4-7

They were lost in commit a4e0defa.

libavfilter/vf_transpose.c

@@ -227,8 +227,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in)
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 
 static const AVOption transpose_options[] = {
-    { "dir", "Transpose direction", OFFSET(dir), AV_OPT_TYPE_INT, { .i64 = TRANSPOSE_CCLOCK_FLIP },
-        TRANSPOSE_CCLOCK_FLIP, TRANSPOSE_CLOCK_FLIP, FLAGS, "dir" },
+    { "dir", "Transpose direction", OFFSET(dir), AV_OPT_TYPE_INT, { .i64 = TRANSPOSE_CCLOCK_FLIP }, 0, 7, FLAGS, "dir" },
         { "cclock_flip", "counter-clockwise with vertical flip", 0, AV_OPT_TYPE_CONST, { .i64 = TRANSPOSE_CCLOCK_FLIP }, .unit = "dir" },
         { "clock",       "clockwise",                            0, AV_OPT_TYPE_CONST, { .i64 = TRANSPOSE_CLOCK       }, .unit = "dir" },
         { "cclock",      "counter-clockwise",                    0, AV_OPT_TYPE_CONST, { .i64 = TRANSPOSE_CCLOCK      }, .unit = "dir" },