avtp: rename tstamp-mode to timestamp-mode

I thnk w cn spre the xtra lttrs.

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29 jobs for master in 51 seconds (queued for 6 seconds)
Status Job ID Name Coverage
  Build Docker
passed #3565864
alpine amd64 manifest builder docker

00:00:21

passed #3565863
android docker

00:00:21

passed #3565862
cerbero fedora amd64 docker

00:00:31

passed #3565861
fedora amd64 docker

00:00:22

passed #3565865
gst-indent amd64 docker

00:00:30

 
  Preparation
passed #3565867
gst indent

00:00:20

manual #3565866
manual
manifest
 
  Build
created #3565876
gstreamer
build cerbero cross-android universal
created #3565880
gst-ios-13.2
build cerbero cross-ios universal
created #3565877
gstreamer
build cerbero cross win32
created #3565878
gstreamer
build cerbero cross win64
created #3565875
gstreamer
build cerbero fedora x86_64
created #3565879
gst-macos-10.15
build cerbero macos x86_64
created #3565871
build clang fedora x86_64
created #3565874
1809 windows docker allowed to fail manual
build msys2
created #3565868
build nodebug fedora x86_64
created #3565869
build static fedora x86_64
created #3565870
build static nodebug fedora x86_64
created #3565872
1809 windows docker
build vs2017 amd64
created #3565873
1809 windows docker
build vs2017 x86
 
  Test
created #3565881
gstreamer
check fedora
created #3565882
gstreamer
integration testsuites fedora 1/4
created #3565883
gstreamer
integration testsuites fedora 2/4
created #3565884
gstreamer
integration testsuites fedora 3/4
created #3565885
gstreamer
integration testsuites fedora 4/4
created #3565886
gstreamer
valgrind bad
 
  Integrate
created #3565887
cross-android universal examples
created #3565889
gst-ios-13.2
cross-ios universal examples
created #3565888
documentation