[dev.simd] simd, cmd/compile: generated code for VPINSR[BWDQ], and test

This is paired with simdgen CL 683055

Change-Id: I91d2c08a97ddd7cf06dd24478d552b962846131c
Reviewed-on: https://go-review.googlesource.com/c/go/+/683035
Reviewed-by: Junyang Shao <shaojunyang@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

Author: dr2chase

src/cmd/compile/internal/amd64/simdssa.go

@@ -1279,6 +1279,14 @@
 (SaturatedUnsignedSignedQuadDotProdAccumulateUint32x16 ...) => (VPDPBUSDS512 ...)
 (SaturatedUnsignedSignedQuadDotProdAccumulateUint32x4 ...) => (VPDPBUSDS128 ...)
 (SaturatedUnsignedSignedQuadDotProdAccumulateUint32x8 ...) => (VPDPBUSDS256 ...)
+(SetElemInt16x8 [a] x y) => (VPINSRW128 [a] x y)
+(SetElemInt32x4 [a] x y) => (VPINSRD128 [a] x y)
+(SetElemInt64x2 [a] x y) => (VPINSRQ128 [a] x y)
+(SetElemInt8x16 [a] x y) => (VPINSRB128 [a] x y)
+(SetElemUint16x8 [a] x y) => (VPINSRW128 [a] x y)
+(SetElemUint32x4 [a] x y) => (VPINSRD128 [a] x y)
+(SetElemUint64x2 [a] x y) => (VPINSRQ128 [a] x y)
+(SetElemUint8x16 [a] x y) => (VPINSRB128 [a] x y)
 (SignInt16x16 ...) => (VPSIGNW256 ...)
 (SignInt16x8 ...) => (VPSIGNW128 ...)
 (SignInt32x4 ...) => (VPSIGND128 ...)