Support cond_{smax,smin,umax,umin} for vector integer modes under AVX512.
gcc/ChangeLog:
* config/i386/sse.md (cond_<code><mode>): New expander.
gcc/testsuite/ChangeLog:
* gcc.target/i386/cond_op_maxmin_b-1.c: New test.
* gcc.target/i386/cond_op_maxmin_b-2.c: New test.
* gcc.target/i386/cond_op_maxmin_d-1.c: New test.
* gcc.target/i386/cond_op_maxmin_d-2.c: New test.
* gcc.target/i386/cond_op_maxmin_q-1.c: New test.
* gcc.target/i386/cond_op_maxmin_q-2.c: New test.
* gcc.target/i386/cond_op_maxmin_ub-1.c: New test.
* gcc.target/i386/cond_op_maxmin_ub-2.c: New test.
* gcc.target/i386/cond_op_maxmin_ud-1.c: New test.
* gcc.target/i386/cond_op_maxmin_ud-2.c: New test.
* gcc.target/i386/cond_op_maxmin_uq-1.c: New test.
* gcc.target/i386/cond_op_maxmin_uq-2.c: New test.
* gcc.target/i386/cond_op_maxmin_uw-1.c: New test.
* gcc.target/i386/cond_op_maxmin_uw-2.c: New test.
* gcc.target/i386/cond_op_maxmin_w-1.c: New test.
* gcc.target/i386/cond_op_maxmin_w-2.c: New test.