Function _mm256_roundscale_ph
#[target_feature(enable = "avx512fp16", enable = "avx512vl")]
pub fn _mm256_roundscale_ph(a: __m256h, IMM8: i32) -> __m256hRound packed half-precision (16-bit) floating-point elements in a to the number of fraction bits specified by imm8, and store the results in dst.
Rounding is done according to the imm8 parameter, which can be one of:
_MM_FROUND_TO_NEAREST_INT: round to nearest_MM_FROUND_TO_NEG_INF: round down_MM_FROUND_TO_POS_INF: round up_MM_FROUND_TO_ZERO: truncate_MM_FROUND_CUR_DIRECTION: useMXCSR.RC- see_MM_SET_ROUNDING_MODE