[Sema] Fix build with GCC

tools/clang/lib/Sema/DeclSpec.cpp: In member function 'void clang::DeclSpec::Finish(clang::Sema&, const clang::PrintingPolicy&)':
tools/clang/lib/Sema/DeclSpec.cpp:1116:8: error: could not convert 'clang::DeclSpec::TSW_unspecified' from 'const TSW {aka const clang::TypeSpecifierWidth}' to 'int'
tools/clang/lib/Sema/DeclSpec.cpp:1117:8: error: could not convert 'clang::DeclSpec::TSW_short' from 'const TSW {aka const clang::TypeSpecifierWidth}' to 'int'
tools/clang/lib/Sema/DeclSpec.cpp:1118:8: error: could not convert 'clang::DeclSpec::TSW_longlong' from 'const TSW {aka const clang::TypeSpecifierWidth}' to 'int'
tools/clang/lib/Sema/DeclSpec.cpp:1128:8: error: could not convert 'clang::DeclSpec::TSW_long' from 'const TSW {aka const clang::TypeSpecifierWidth}' to 'int'

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@321626 91177308-0d34-0410-b5e6-96231b3b80d8