i965: Make L3 configuration atom listen for TCS/TES program updates.

The L3 configuration code already considers the TCS and TES programs,
but failed to listen for TCS/TES program changes.

This was somehow missing.

Fixes: e9644cb1 ("i965: Consider tessellation in get_pipeline_state_l3_weights.")
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
(cherry picked from commit b8d42ccc)