rtspsrc: Remove uneeded keep-alive hack

The rtsp connection code has been fixed now.

https://bugzilla.gnome.org/show_bug.cgi?id=744209
15 jobs for 744209-keep-alive in 55 minutes and 12 seconds (queued for 2 seconds)
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  Preparation
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gst indent

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manifest

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  Build
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build fedora x86_64

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build nodebug fedora x86_64

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check fedora

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integration testsuites fedora

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build cerbero android universal

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build cerbero cross win32

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build cerbero cross win64

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build cerbero fedora x86_64

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valgrind bad

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valgrind ges

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android universal examples

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documentation

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