Revert "msm: display: Do not commit in unset for external."

This reverts commit e23729eaae21cf37781142611a1edec86bee7c5a.

Revert "msm: mdp: Wait unconditionally in internal vsync waits"

This reverts commit 8f4ed8e2f33c662acf71f246a9dab689c44251e3.

Revert "msm: mdp: Use a waitqueue for vsync notifications"

This reverts commit 1b835d2d5d1e612774c613150fd2cb75b10a626d.