i965: Track fast color clear state in level/layer granularity

i965: Track fast color clear state in level/layer granularity

Note that RESOLVED is not tracked in the map explicitly. Absence
of item implicitly means RESOLVED state.

v2: Added intel_resolve_map_clear() into intel_miptree_release()
v3 (Jason): Properly handle the assumption of resolve map not
            containing any items with state RESOLVED. Removed
            unnecessary intel_miptree_set_fast_clear_state() call
            in brw_blorp_resolve_color() preventing
            intel_miptree_set_fast_clear_state() from asserting
            against RESOLVED.

Signed-off-by: Topi Pohjolainen <topi.pohjolainen@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>