asahi: Fix BIND_PIPELINE sizing and alignment

asahi: Fix BIND_PIPELINE sizing and alignment

Fix a bug in BIND_PIPELINE XML reported by Dougall, which cleans up
a bit of both decoder and driver.

Instead of...

   * 17 bytes BIND_PIPELINE  (17)
   * An unused 8 byte record (25)
   * A set of N 8 byte records (25 + 8 * N)
   * Oops, 1 byte too many! One just disappeared (24 + 8 * N)

It seems to instead be

   * 24 bytes BIND_PIPELINE (24)
   * A set of N 8 byte records (24 + 8 * N)

without the sentinel record. These means the 8 byte records themselves
are shuffled, with the high byte of the pointers split from the low
word, but that's less gross than an off-by-one.

It's still not clear what the last 8 bytes of the BIND_VERTEX_PIPELINE
structure mean, or the last 4 byte of the BIND_FRAGMENT_PIPELINE
structure which seems to be a bit shorter.

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13784>