To run the test suite for xcb-xkb, you will need to have the Check unit testing framework installed. 
Also make sure you have an XKB aware version of libxcb and xcb-proto, they can be obtained from 
http://cgit.freedesktop.org/~chr/libxcb/
http://cgit.freedesktop.org/~chr/xcb_proto/

To run the tests, type

./configure

then

make check

The code in xkb_util.[hc] might be useful outside the test module, it is however not intended to be complete or extremely user friendly. 

Please report bugs to oss@arcor.de