[clang][LoongArch] Introduce LASX and LSX conversion intrinsics
This patch introduces the LASX and LSX conversion intrinsics:
- __m256 __lasx_cast_128_s (__m128)
- __m256d __lasx_cast_128_d (__m128d)
- __m256i __lasx_cast_128 (__m128i)
- __m256 __lasx_concat_128_s (__m128, __m128)
- __m256d __lasx_concat_128_d (__m128, __m128d)
- __m256i __lasx_concat_128 (__m128, __m128i)
- __m128 __lasx_extract_128_lo_s (__m256)
- __m128d __lasx_extract_128_lo_d (__m256d)
- __m128i __lasx_extract_128_lo (__m256i)
- __m128 __lasx_extract_128_hi_s (__m256)
- __m128d __lasx_extract_128_hi_d (__m256d)
- __m128i __lasx_extract_128_hi (__m256i)
- __m256 __lasx_insert_128_lo_s (__m256, __m128)
- __m256d __lasx_insert_128_lo_d (__m256d, __m128d)
- __m256i __lasx_insert_128_lo (__m256i, __m128i)
- __m256 __lasx_insert_128_hi_s (__m256, __m128)
- __m256d __lasx_insert_128_hi_d (__m256d, __m128d)
- __m256i __lasx_insert_128_hi (__m256i, __m128i)