broadcom/qpu: new packing/conversion v71 instructions

broadcom/qpu: new packing/conversion v71 instructions

This commits adds the qpu definitions for several new v71
instructions.

Packing:
  * vpack does a 2x32 to 2x16 bit integer pack
  * v8pack: Pack 2 x 2x16 bit integers into 4x8 bits
  * v10pack packs parts of 2 2x16 bit integer into r10g10b10a2.
  * v11fpack packs parts of 2 2x16 bit float into r11g11b10 rounding
    to nearest

Conversion to unorm/snorm:
  * vftounorm8/vftosnorm8: converts from 2x16-bit floating point
    to 2x8 bit unorm/snorm.
  * ftounorm16/ftosnorm16: converts floating point to 16-bit
    unorm/snorm
  * vftounorm10lo: Convert 2x16-bit floating point to 2x10-bit unorm
  * vftounorm10hi: Convert 2x16-bit floating point to one 2-bit and one 10-bit unorm

Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25450>