Fix compilation of qocamlbrowser and add new version

[Kakadu]

old version restricted to < 4.04
new one added

Inspired by #9915

[yallop]

The Travis job for OCaml 4.05.0 is failing to build lablqt.0.4:

# File "ppxext/ppx_qt.ml", line 246, characters 79-88:
# Error: This expression has type string but an expression was expected of type
#          Ast_helper.str = string Location.loc
# Command exited with code 2.

I've opened a separate PR (#9942) to fix the problem.

[avsm]

I think this is fine to merge now that #9915 has also been merged