MdePkg/UefiLib: Correct the arguments passed to IsLanguageSupported()

MdePkg/UefiLib: Correct the arguments passed to IsLanguageSupported()

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3211

Correct the arguments passed to the IsLanguageSupported() function in
AddUnicodeString2() and LookupUnicodeString2() as expected by the function

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: Chandramohan Akula <chandramohan.akula@broadcom.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>