Update wxGTK.spec to work with openSUSE build server.

Update wxGTK.spec to work with openSUSE build server.

Changes from Marcin Wojdyr fixing issues for different RPM-using systems:

- added all necessary BuildRequires fields
- for openSuse wxGTK-gl package is named libwx_gtk*_gl... (it's
enforced that package with one shared lib has name matching the
library name)
- added missing '%dir's - on some distros rpms didn't built without it
- Fedora, Suse and Mandriva have all different set of known Groups,
I've changed group from 'X11/Libraries' to 'System/Libraries' -- it's
defined at least in Suse and Mandriva. (in recent distro releases
Group can be skipped, so it's becoming irrelevant).
- removed 'Packager' field and dots ending Summary field - AFAIR these
were errors on Opensuse
- added '= %{version}' to Provides
- for Redhat5 use GCC4.4 (build crashed with default 4.2)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72508 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775