The yast2-theme package makes a syslink to the hicolor directory instead of
oxygen by default:
# let's take hicolor icons for yast
ln -s /usr/share/icons/hicolor $RPM_BUILD_ROOT%{yast_themedir}/current/icons
Furthermore, the yast2-theme version shipped on 13.2 RC1 doesn't have %posts as
the version shipped on 13.1:
%post openSUSE-Oxygen
cd /usr/share/YaST2/theme
ln -snf openSUSE-Oxygen openSUSE-current