trace: separate MMIO tracepoints from TB-access tracepoints

Memory accesses to code which has previously been translated into a TB show up
in the MMIO path, so that they may invalidate the TB. It's extremely confusing
to mix those in with device MMIOs, so split them into their own tracepoint.

Signed-off-by: Hollis Blanchard <hollis_blanchard@mentor.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1456949575-1633-2-git-send-email-hollis_blanchard@mentor.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
