.python/SpellCheck: Add "Loongson" and "LOONGARCH" to "words" section
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4053
Add Loongson and LOONGARCH to "words" section in cspell.base.yaml file
to avoid spelling check error.
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Signed-off-by: Chao Li <lichao@loongson.cn>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>