xkbcomp: update to 1.4.1.

This release adds the path of the xkbcomp executable to the pkgconfig
data, allowing the X server to find the right binary regardless of
where its (the X servers) $prefix is pointed. Without this the X server
will guess that xkbcomp is configured for the same prefix; since the
default prefix is /usr/local, and your distribution certainly did not
install xkbcomp there, 'make check' and 'ninja dist' for the X server
build would fail because Xvfb would not start.

xkbcomp itself has no functional changes in this release.

(wiz)