[RISCV] Add IMinMax sched resources to P600SchedModel
CI checks were passing in #84962 (c48d8182f172ac24244d5fb038b7ab983f67def4) but
that commit caused failures once merged due to ships passing since the
PR was not rebased on #85131. This commit fixes this problem by adding
sched resources for integer min max instructions from Zbb in P600 model.
