Revert "[MMFMWK-7873] glimagesink: need add glFinish after eglswapbuffer"

This is the wrong way to fix tearing as it will stall the rendering
pipeline. https://bugzilla.gnome.org/show_bug.cgi?id=791937

No tearing visible with this reverted, but performance goes up from
23 to 29 fps in one particular test.

This reverts commit d20d23dc4cb100479d1edb627b4cf14d45998923.
1 file changed