This will let us implement XkbAtomGetString on top of XkbAtomText,
instead of having the latter get a duplicated string, dump it into a
temporary buffer, and subsequently free it (sigh).
Signed-off-by: Daniel Stone <daniel@fooishbar.org>
Copy over the Xkb_RF* rules parsing functions from xkbfile's maprules.c.
Eventually, this will be tied into xkbcomp's path searching utilities so
you don't need to supply a full path to the rules file. Also, it this
should eventually incorporate the server's RMLVOSet.
Following the kbproto convention, the headers will be named XKBcommon.h
and XKBcommonint.h. Furthermore, they'll be installed in X11/extensions
directory with the rest of the XKB headers.