[LoongArch] Implement isLegalAddressingMode for lsx/lasx#151917

zhaoqi5 wants to merge 2 commits intousers/zhaoqi5/test-vec-addressmodellvm/llvm-project:users/zhaoqi5/test-vec-addressmodefrom

users/zhaoqi5/vec-legaladdressingmodellvm/llvm-project:users/zhaoqi5/vec-legaladdressingmodeCopy head branch name to clipboard