package/gst1-libav: bump version to 1.20.0

- update COPYING hash (license text update from LGPL-2.0+ to LGPL-2.1+,
  see [1]) and adjust GST1_LIBAV_LICENSE accordingly

[1] https://gitlab.freedesktop.org/gstreamer/gstreamer/-/commit/d157b23fb0ce175b167611a4cb019599d9017042.patch

Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/gstreamer1/gst1-libav/gst1-libav.hash

@@ -1,3 +1,3 @@
-# From https://gstreamer.freedesktop.org/src/gst-libav/gst-libav-1.18.6.tar.xz.sha256sum
-sha256  e4e50dcd5a29441ae34de60d2221057e8064ed824bb6ca4dc0fd9ee88fbe9b81  gst-libav-1.18.6.tar.xz
-sha256  f445dc78b88496f7e20c7a2a461b95baba5865c8919b8289ac24ac0a80c6ce7a  COPYING
+# From https://gstreamer.freedesktop.org/src/gst-libav/gst-libav-1.20.0.tar.xz.sha256sum
+sha256  5eee5ed8d5082a31b500448e41535c722ee30cd5f8224f32982bbaba2eedef17  gst-libav-1.20.0.tar.xz
+sha256  ad2eec519ebd4b5df86ea84dff24ae3bfa2edea846a703b58902dd221ae375db  COPYING

package/gstreamer1/gst1-libav/gst1-libav.mk

@@ -4,10 +4,10 @@
 #
 ################################################################################
 
-GST1_LIBAV_VERSION = 1.18.6
+GST1_LIBAV_VERSION = 1.20.0
 GST1_LIBAV_SOURCE = gst-libav-$(GST1_LIBAV_VERSION).tar.xz
 GST1_LIBAV_SITE = https://gstreamer.freedesktop.org/src/gst-libav
-GST1_LIBAV_LICENSE = LGPL-2.0+
+GST1_LIBAV_LICENSE = LGPL-2.1+
 GST1_LIBAV_LICENSE_FILES = COPYING
 GST1_LIBAV_DEPENDENCIES =  host-pkgconf ffmpeg gstreamer1 gst1-plugins-base
 GST1_LIBAV_CONF_OPTS = -Ddoc=disabled