v4l2bufferpool: do not queue released buffers on an orphaned pool

When a buffer pool is orphaned, we expect its buffers to be released
some time later, when their reference count drops to zero. There is
nothing to be done in the release function. Specifically, the buffers
must not be queued back into the already released V4L2 queue.
19 jobs for v4l2bufferpool-orphan-release in 36 minutes and 32 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Preparation
passed #372227
gst indent

00:00:29

passed #372226
manifest

00:00:21

 
  Build
passed #372233
build cerbero android universal

00:11:49

passed #372234
build cerbero cross win32

00:09:34

passed #372235
build cerbero cross win64

00:08:06

passed #372232
build cerbero fedora x86_64

00:09:17

manual #372237
gst-ios-12.2 allowed to fail manual
build cerbero ios universal
passed #372236
gst-macos-10.14
build cerbero macos x86_64

00:07:08

passed #372228
build fedora x86_64

00:08:14

passed #372229
build nodebug fedora x86_64

00:05:26

passed #372230
build static fedora x86_64

00:14:00

passed #372231
build static nodebug fedora x86_64

00:12:37

 
  Test
passed #372238
check fedora

00:06:52

passed #372239
integration testsuites fedora

00:15:12

passed #372241
valgrind bad

00:06:28

passed #372242
valgrind ges

00:05:06

passed #372240
valgrind good

00:13:46

 
  Integrate
passed #372243
android universal examples

00:06:49

passed #372244
documentation

00:03:46