pkgconfig: fix gstreamer-plugins-base-1.0 .pc files for no OpenGL case

Don't put gl into the libraries list if the gst-gl library isn't
being built, and also don't include it in the list of linker flags
then.

Fixes gstreamer/gst-plugins-base#613

Part-of: <gstreamer/gst-plugins-base!742>
33 jobs for !742 with fix-gstreamer-plugins-base-pc-for-no-gl in 24 minutes and 31 seconds (queued for 39 seconds)
detached
Status Job ID Name Coverage
  Build Docker
passed #3508055
alpine amd64 manifest builder docker

00:00:30

passed #3508054
android docker

00:00:21

passed #3508052
cerbero fedora amd64 docker

00:00:27

passed #3508051
fedora amd64 docker

00:00:20

passed #3508057
gst-indent amd64 docker

00:00:27

 
  Preparation
passed #3508060
gst indent

00:00:22

passed #3508058
manifest

00:00:59

 
  Build
passed #3508078
gstreamer
build cerbero cross-android universal

00:05:05

passed #3508082
gst-ios-13.2
build cerbero cross-ios universal

00:21:00

passed #3508079
gstreamer
build cerbero cross win32

00:06:08

passed #3508080
gstreamer
build cerbero cross win64

00:04:05

passed #3508076
gstreamer
build cerbero fedora x86_64

00:03:42

passed #3508081
gst-macos-10.15
build cerbero macos x86_64

00:09:08

passed #3508067
build clang fedora x86_64

00:06:49

manual #3508073
docker windows 1809 allowed to fail manual
build msys2
passed #3508062
build nodebug fedora x86_64

00:03:56

passed #3508063
build static fedora x86_64

00:03:21

passed #3508065
build static nodebug fedora x86_64

00:02:57

passed #3508068
docker windows 1809
build vs2017 amd64

00:13:16

passed #3508071
docker windows 1809
build vs2017 x86

00:13:15

 
  Test
passed #3508083
gstreamer
check fedora

00:05:09

passed #3508084
gstreamer
integration testsuites fedora 1/4

00:12:13

passed #3508085
gstreamer
integration testsuites fedora 2/4

00:13:15

passed #3508086
gstreamer
integration testsuites fedora 3/4

00:12:32

passed #3508087
gstreamer
integration testsuites fedora 4/4

00:15:11

passed #3508091
gstreamer
valgrind bad

00:04:27

passed #3508088
gstreamer
valgrind base

00:04:44

passed #3508092
gstreamer
valgrind ges

00:08:49

passed #3508089
gstreamer
valgrind good

00:08:06

passed #3508090
gstreamer
valgrind ugly

00:03:06

 
  Integrate
passed #3508093
cross-android universal examples

00:06:27

passed #3508095
gst-ios-13.2
cross-ios universal examples

00:01:28

passed #3508094
documentation

00:08:55