Update VfrCompiler to fix the following incompatible and check issues.

Update VfrCompiler to fix the following incompatible and check issues.
     1. First structure name will be declared as the default buffer varstore if no any buffer varstore is declared.
     2. Use numeric IFR type to declare the undefined question in order to support the different data type.
     3. Array check for CheckBox, Nemeric and Oneof Type, because they don't support the array as their question.
     4. Check the index in array for UEFI and Framework VFR question.

git-svn-id: https://buildtools.tianocore.org/svn/buildtools/trunk/BaseTools@1320 7335b38e-4728-0410-8992-fb3ffe349368