bug#15392: xorg-server FTBFS

[Mark H Weaver <mhw@netris.org>]

Hello all,

xorg-server fails to build from source.  See below for the tail of the
build log.  This is with aae4ead8142d4fd7c674a1e6e302f40469f878c6.

    Regards,
      Mark


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PASS: input
XKB: Failed to compile keymap
Keyboard initialization failed. This could be a missing or incorrect setup of xkeyboard-config.

Fatal server error:
Failed to activate core devices.

Please consult the The X.Org Foundation support
         at http://wiki.x.org
 for help.

FAIL: xtest
PASS: misc
PASS: fixes
PASS: xfree86
========================================================================
1 of 9 tests failed
Please report to https://bugs.freedesktop.org/enter_bug.cgi?product=xorg
========================================================================
make[3]: *** [check-TESTS] Error 1
make[3]: Leaving directory `/tmp/nix-build-xorg-server-1.12.2.drv-0/xorg-server-1.12.2/test'
make[2]: *** [check-am] Error 2
make[2]: Leaving directory `/tmp/nix-build-xorg-server-1.12.2.drv-0/xorg-server-1.12.2/test'
make[1]: *** [check-recursive] Error 1
make[1]: Leaving directory `/tmp/nix-build-xorg-server-1.12.2.drv-0/xorg-server-1.12.2/test'
make: *** [check-recursive] Error 1
phase `check' failed after 2 seconds
builder for `/nix/store/kgpvhgf4rin7syv7cxid78vmlckqqyfg-xorg-server-1.12.2.drv' failed with exit code 1
@ build-failed /nix/store/kgpvhgf4rin7syv7cxid78vmlckqqyfg-xorg-server-1.12.2.drv - 1 builder for `/nix/store/kgpvhgf4rin7syv7cxid78vmlckqqyfg-xorg-server-1.12.2.drv' failed with exit code 1
guix package: error: build failed: build of `/nix/store/kgpvhgf4rin7syv7cxid78vmlckqqyfg-xorg-server-1.12.2.drv' failed
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