Fix SIMD Scalar Move Encoding: VEX.L should be 0

Fix SIMD Scalar Move Encoding: VEX.L should be 0

For SIMD Scalar Move instructions such as vmovlpd, vmovlps, vmovhps,
vmovhps and vmovss on AVX system, JIT should ensure that those
instructions are encoded with VEX.L=0, because encoding them with
VEX.L=1 may encounter unpredictable behavior across different
processor generations. The reason of VEX.L is encoded with 1 is
because JIT calls compiler->getSIMDVectorType() which returns
EA_32BYTE, and it is been passed into emitter AddVexPrefix() which
ends up encoded VEX.L=1, the fix is to pass target type and base
type for those instructions to ensure that VEX.L=0 at emitter
AddVexPrefix()

Fix #8328