i965/fs: Use inst->eot rather than opcodes in register allocation.

i965/fs: Use inst->eot rather than opcodes in register allocation.

Previously, we special cased FB writes and URB writes in the register
allocation code.  What we really wanted was to handle any message with
EOT set.

This saves us from extending the list with new opcodes in the future.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>