[compiler-rt][profile][RISCV] Enable profile for RISC-V

Profile library are written by standard libraries or POSIX calls depend on target support, so there is no porting effort for the target, we could enable that for both RV32 and RV64, verified on the RV64 platform.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D124599