MacOSX symbol table change to combine the N_GSYM debug map entry with the...

MacOSX symbol table change to combine the N_GSYM debug map entry with the "_OBJC_CLASS_$_", "_OBJC_METACLASS_$_", and "_OBJC_IVAR_$_" non debug symbols. This allows the symbol that represents the object file to contain the eSymbolTypeObjCClass and eSymbolTypeObjCMetaClass and will help us to be able to efficiently lookup the real definition of an objective C class without loading all .o files linearly to find the .o file that contains the true definition.

llvm-svn: 230509