Adding PeiServicesTablePointerLibKs0 for LoongArch64, which provides
setting and getting the PEI service table pointer through the CSR KS0
register.
The idea of this library is derived from
ArmPkg/Library/PeiServicesTablePointerLib/
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4584
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Zhiguang Liu <zhiguang.liu@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Chao Li <lichao@loongson.cn>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>