eglimage: Fix extension names in dmabuf import check

There was a typo in the extension name which resulted in the modifiers
to never be set when doing DMABuf import. That triggered the modifiers
lookup in Intel driver, which was in fact hiding bugs in the gldownload
to glupload path when doing DMABuf.

Note, this changes breaks pipeline the following pipeline on Intel and
some other drivers:

  gltestsrc ! gldownload ! video/x-raw\(memory:DMABuf\) ! glimagsink

A fix for this was added to Mesa recently:

Related to mesa/mesa!1338
Fixes 5d0e1917
21 jobs for gl-dmabuf-export-fix in 55 minutes and 39 seconds (queued for 3 seconds)
latest
Status Job ID Name Coverage
  Preparation
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gst indent

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manifest

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  Build
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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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gst-ios-12.2 allowed to fail manual
build cerbero ios universal
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gst-macos-10.14
build cerbero macos x86_64

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build fedora x86_64

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build nodebug fedora x86_64

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build static fedora x86_64

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passed #470335
build static nodebug fedora x86_64

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  Test
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check fedora

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integration testsuites fedora

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valgrind bad

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valgrind base

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valgrind ges

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valgrind good

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  Integrate
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android universal examples

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documentation

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