anv: Apply any needed PIPE_CONTROLs before emitting state

anv: Apply any needed PIPE_CONTROLs before emitting state

Push constants in particular can get picked up by the hardware at weird
times that happen *before* 3DPRIMITIVE.  Therefore, we need to flush
before we emit all our state to ensure that any data they may pick up is
in memory in time.  This fixes an app which does vkCmdCopyBuffers
immediately followed by a vkCmdBeginRenderPass and vkCmdDraw which uses
the destination of the copy as a UBO which we push.

Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4601>