git: openjdk/jfx11u: master: 8288450: Update attribution in gstreamer.md file

[Kevin Rushforth]

Changeset: 53d18fc5
Author:    Kevin Rushforth <kcr at openjdk.org>
Date:      2022-08-23 18:08:18 +0000
URL:       https://git.openjdk.org/jfx11u/commit/53d18fc535d4426ec604c0e0d1b5138b5f36dde5

8288450: Update attribution in gstreamer.md file
8288449: Update attribution in glib.md file

Backport-of: 54e689ce639ee182113dab610d9ed82890493898

! modules/javafx.media/src/main/legal/glib.md
! modules/javafx.media/src/main/legal/gstreamer.md
- modules/javafx.media/src/main/native/gstreamer/3rd_party/glib/glib/valgrind.h