i965: Use aubinator/genxml for INTEL_DEBUG=bat state decoding.

i965: Use aubinator/genxml for INTEL_DEBUG=bat state decoding.

This deletes all of our handwritten code in favor of autogenerated
genxml-based decoding.  This should be much more usable, as the old
code isn't entirely accurate - we updated some things for new
generations, but not everything.

Aubinator has one annoying limitation: it has no idea how many entries
to print when encountering e.g. 3DSTATE_BINDING_TABLE_POINTERS_VS.  It
picks an arbitrary number, which may skip decoding valid data, and may
print extra garbage entries.

We do a better job here by making brw_state_batch track the size of the
data stored at a particular batchbuffer offset.  Then, we can divide by
the structure size to obtain the exact number of entries.

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>