configure: update minimum required version of libvmaf

At least version 0.6.2 is needed since commit
df3222d4bb.

Reviewed-by: Ronald S. Bultje <rsbultje@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>

configure

@@ -5911,7 +5911,7 @@ enabled libtwolame        && require libtwolame twolame.h twolame_init -ltwolame
                                die "ERROR: libtwolame must be installed and version must be >= 0.3.10"; }
 enabled libv4l2           && require_pkg_config libv4l2 libv4l2 libv4l2.h v4l2_ioctl
 enabled libvidstab        && require_pkg_config libvidstab "vidstab >= 0.98" vid.stab/libvidstab.h vsMotionDetectInit
-enabled libvmaf           && require_pkg_config libvmaf libvmaf libvmaf.h compute_vmaf
+enabled libvmaf           && require_pkg_config libvmaf "libvmaf >= 0.6.2" libvmaf.h compute_vmaf
 enabled libvo_amrwbenc    && require libvo_amrwbenc vo-amrwbenc/enc_if.h E_IF_init -lvo-amrwbenc
 enabled libvorbis         && require_pkg_config libvorbis vorbis vorbis/codec.h vorbis_info_init &&
                              require_pkg_config libvorbisenc vorbisenc vorbis/vorbisenc.h vorbis_encode_init