[RISCV] Add sched to pseudo function call instructions

To fix llvm-mca's error of 'found an unsupported instruction
in the input assembly sequence.' caused by the lack of
scheduling info.

Pseudo function call instructions will be expanded to `auipc`
and `jalr`, so their scheduling info are the combination of
two.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D123578