iris/anv: Reduce PIPELINE_CONTROL flushes when switching pipeline mode for TGL and newer
Intel CI is happy with it https://mesa-ci.01.org/josouza/builds/87/group/63a9f0ea7bb98050796b649e85481845
Probably some performance gains in applications that frequently changes pipeline mode.
anv: Split emit_apply_pipe_flushes() into GFX_VER >= 12 and older
is a minor suggestion, if someone don't like it I can drop it.
Edited by José Roberto de Souza