avdevice/v4l2: use AV_OPT_TYPE_BOOL for use_libv4l2 option

libavdevice/v4l2.c

@@ -1112,7 +1112,7 @@ static const AVOption options[] = {
     { "default",      "use timestamps from the kernel",                           OFFSET(ts_mode),      AV_OPT_TYPE_CONST,  {.i64 = V4L_TS_DEFAULT  }, 0, 2, DEC, "timestamps" },
     { "abs",          "use absolute timestamps (wall clock)",                     OFFSET(ts_mode),      AV_OPT_TYPE_CONST,  {.i64 = V4L_TS_ABS      }, 0, 2, DEC, "timestamps" },
     { "mono2abs",     "force conversion from monotonic to absolute timestamps",   OFFSET(ts_mode),      AV_OPT_TYPE_CONST,  {.i64 = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" },
-    { "use_libv4l2",  "use libv4l2 (v4l-utils) conversion functions",             OFFSET(use_libv4l2),  AV_OPT_TYPE_INT,    {.i64 = 0}, 0, 1, DEC },
+    { "use_libv4l2",  "use libv4l2 (v4l-utils) conversion functions",             OFFSET(use_libv4l2),  AV_OPT_TYPE_BOOL,   {.i64 = 0}, 0, 1, DEC },
     { NULL },
 };