configure: update libvpx_vp9_encoder check

Required to add support for the aq_mode setting.
Any libvpx snapshot prior to 1.3.0 is not recommended for vp9 encoding for that matter.
Reviewed-by: James Zern <jzern@google.com>
Signed-off-by: James Almer <jamrial@gmail.com>

configure

@@ -4846,7 +4846,7 @@ enabled libvpx            && {
     enabled libvpx_vp8_encoder && { check_lib2 "vpx/vpx_encoder.h vpx/vp8cx.h" "vpx_codec_enc_init_ver VP8E_SET_MAX_INTRA_BITRATE_PCT" -lvpx ||
                                     die "ERROR: libvpx encoder version must be >=0.9.7"; }
     enabled libvpx_vp9_decoder && { check_lib2 "vpx/vpx_decoder.h vpx/vp8dx.h" "vpx_codec_vp9_dx" -lvpx || disable libvpx_vp9_decoder; }
-    enabled libvpx_vp9_encoder && { check_lib2 "vpx/vpx_encoder.h vpx/vp8cx.h" "vpx_codec_vp9_cx VP9E_SET_SVC" -lvpx || disable libvpx_vp9_encoder; } }
+    enabled libvpx_vp9_encoder && { check_lib2 "vpx/vpx_encoder.h vpx/vp8cx.h" "vpx_codec_vp9_cx VP9E_SET_AQ_MODE" -lvpx || disable libvpx_vp9_encoder; } }
 enabled libwavpack        && require libwavpack wavpack/wavpack.h WavpackOpenFileOutput  -lwavpack
 enabled libwebp           && require_pkg_config libwebp webp/encode.h WebPGetEncoderVersion &&
                              { check_code cc webp/encode.h "WebPPicture wp; wp.use_argb++" ||