This library is required to make SBI ecalls from the S-mode EDK2.
This is mostly copied from
edk2-platforms/Silicon/RISC-V/ProcessorPkg/Library/RiscVEdk2SbiLib
Cc: Michael D Kinney <michael.d.kinney@intel.com> Cc: Liming Gao <gaoliming@byosoft.com.cn> Cc: Zhiguang Liu <zhiguang.liu@intel.com> Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> Acked-by: Abner Chang <abner.chang@amd.com> Reviewed-by: Andrei Warkentin <andrei.warkentin@intel.com> Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>