[llvm][AArch64][Assembly]: Add LUT assembly/disassembly. (#70802)

This patch adds the feature flags of LUT and SME_LUTv2, and the
assembly/disassembly
for the following instructions of NEON, SVE2 and SME2:
  * NEON: 
    - LUT2
    - LUT4
  * SVE2:
    - LUTI2_ZZZI
    - LUTI4_ZZZI 
    - LUTI4_Z2ZZI
  * SME: 
     - MOVT
     - LUTI4_4ZZT2Z
     - LUTI4_S_4ZZT2Z

That is according to this documentation:
https://developer.arm.com/documentation/ddi0602/2023-09