Testing the texture read performance shows that the same tuning for
the SQ credits is needed on GLK as on BXT/APL. This has been also
confirmed by Altug from the HW team.

V4: Rebase + fix
Signed-off-by: NValtteri Rantala <valtteri.rantala@intel.com>
Reviewed-by: David Weinehall <david.weinehall@linux.intel.com> (v1)
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1511880305-12166-1-git-send-email-valtteri.rantala@intel.com