anv: Keep track of whether the data cache should be enabled in L3

anv: Keep track of whether the data cache should be enabled in L3

If images or shader buffers are used, we will enable the data cache in
the the L3 config.

Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>