opengl: fix warning on talloc_free

Whatever.
11 jobs for v3.104.0 in 9 minutes and 41 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Build
passed #513418
aarch64 docker
build-aarch64

00:00:24

passed #513419
macos
build-macos

00:00:09

passed #513414
amd64 docker
build-ubuntu

00:00:41

passed #513415
amd64 docker
build-ubuntu-static

00:01:00

passed #513416
amd64 docker
build-win32

00:00:19

passed #513417
amd64 docker
build-win64

00:00:09

 
  Test
passed #513421
gpu
test-gpu

00:01:53

76.0033%
passed #513422
gpu
test-gpu-asan

00:02:19

passed #513423
gpu
test-gpu-msan

00:01:56

passed #513424
gpu
test-gpu-ubsan

00:02:04

passed #513420
amd64 docker
test-ubuntu-scan

00:00:24