xwayland: Explicitly link with xcb-shape

XWM uses xcb-shape as of 332d1892bb, to exclude the shadow from the
input region. However, it does not explicitly link xcb-shape for the new
symbols; on one of my machines this is pulled in as a transient
dependency (masking the issue), but apparently not the other.

Solve it by explicitly linking xcb-shape and requiring it in configure.

Signed-off-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Quentin Glidic <sardemff7+git@sardemff7.net>
Fixes: 332d1892bb ("xwm: do not include shadow in input region")
Cc: Ian Ray <ian.ray@ge.com>

configure.ac

@@ -168,7 +168,7 @@ AC_ARG_ENABLE(xwayland-test, [  --enable-xwayland-test],,
 AM_CONDITIONAL(ENABLE_XWAYLAND, test x$enable_xwayland = xyes)
 AM_CONDITIONAL(ENABLE_XWAYLAND_TEST, test x$enable_xwayland = xyes -a x$enable_xwayland_test = xyes)
 if test x$enable_xwayland = xyes; then
-  PKG_CHECK_MODULES([XWAYLAND], xcb xcb-xfixes xcb-composite xcursor cairo-xcb)
+  PKG_CHECK_MODULES([XWAYLAND], xcb xcb-xfixes xcb-composite xcb-shape xcursor cairo-xcb)
   AC_DEFINE([BUILD_XWAYLAND], [1], [Build the X server launcher])
 
   AC_ARG_WITH(xserver-path, AS_HELP_STRING([--with-xserver-path=PATH],