[XCCDF] Fixed parsing choices and exporting mustMatch attribute
[XCCDF] Fixed parsing choices and exporting mustMatch attribute

mpreisler/openscap,OpenSCAP/openscap,openprivacy/openscap,Hexadorsimal/openscap,isimluk/openscap,isimluk/openscap,postfix/openscap,openprivacy/openscap,ybznek/openscap,redhatrises/openscap,OpenSCAP/openscap,jan-cerny/openscap,isimluk/openscap,redhatrises/openscap,OpenSCAP/openscap,ybznek/openscap,openprivacy/openscap,postfix/openscap,OpenSCAP/openscap,isimluk/openscap,Hexadorsimal/openscap,ybznek/openscap,mpreisler/openscap,jan-cerny/openscap,postfix/openscap,Hexadorsimal/openscap,isimluk/openscap,jan-cerny/openscap,postfix/openscap,redhatrises/openscap,isimluk/openscap,redhatrises/openscap,mpreisler/openscap,redhatrises/openscap,mpreisler/openscap,Hexadorsimal/openscap,OpenSCAP/openscap,mpreisler/openscap,Hexadorsimal/openscap,postfix/openscap,jan-cerny/openscap,ybznek/openscap,openprivacy/openscap,jan-cerny/openscap,ybznek/openscap,mpreisler/openscap,jan-cerny/openscap,ybznek/openscap,OpenSCAP/openscap,postfix/openscap,redhatrises/openscap,openprivacy/openscap,Hexadorsimal/openscap,openprivacy/openscap