panfrost: Free hash_to_temp map

panfrost: Free hash_to_temp map

No need to put it on the context, we can keep it local in mir_squeeze
and drop when we're done.

15.77KB leaked over 85 calls from:
    0xffffaed3bfc3
      in ??
    _mesa_hash_table_rehash
      at ../src/util/hash_table.c:368
      in /home/alyssa/rockchip_dri.so
    hash_table_insert
      at ../src/util/hash_table.c:403
      in /home/alyssa/rockchip_dri.so
    find_or_allocate_temp
      at ../src/panfrost/midgard/mir_squeeze.c:48
      in /home/alyssa/rockchip_dri.so
    find_or_allocate_temp
      at ../src/panfrost/midgard/mir_squeeze.c:35
      in /home/alyssa/rockchip_dri.so
    mir_squeeze_index
      at ../src/panfrost/midgard/mir_squeeze.c:76

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Cc: mesa-stable
Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6373>