[RISCV] Use ComplexPattern to reduce the number of patterns for XVentanaCondOps.

XVentanaCondOps check the condition operand for zero or non-zero.
We use this to optimize seteq/setne that would otherwise becomes
xor/xori/addi+snez/seqz. These patterns avoid the snez/seqz.

This patch adds two ComplexPatterns to match the varous cases and
emit the xor/xori/addi instruction.

These patterns can also be used by D144681.

Reviewed By: philipp.tomsich

Differential Revision: https://reviews.llvm.org/D144700