sse.md (*vec_concatv2sf_sse4_1): New insn pattern.
* config/i386/sse.md (*vec_concatv2sf_sse4_1): New insn pattern.
(*vec_concatv2si_sse4_1): Use vector_move_operand predicate
for operand 2. Remove pinsr{q,d} with 0x0 immediate operand from
insn alternatives. Add missing alternatives.
(*vec_concatv2di_rex64_sse4_1): Likewise.
(*vec_concatv2si_sse2): Use "x" register constraint instead of "Y2".
(*vec_concatv2di_rex64_sse): Rename from *vec_concatv2di_rex64.
Require TARGET_SSE.