Fix for Mantis #19697. For this we need to have the internal static var symbol know that it came from a static field var symbol so that we can check that for generic or not.

symsym.pas, tfieldvarsym:
  + add new field fieldvarsym which holds a reference to a tfieldvarsym if the static sym was created based on such a symbol
  + add necessary methods and code to correctly load from and store to PPU
  + add new constructor create_from_fieldvar
symcreat.pas, make_field_static: 
  * use new create_from_fieldvar constructor instead of the default one
hlcgobj.pas, finalize_static_data:
  * check whether the static var is based on a generic's class var
ppu.pas:
  * increase PPU version

+ added test

git-svn-id: trunk@27466 -