build: Add GLib requirement

For consistency with other components and for the GLib macros set by
XDT_CHECK_PACKAGE when building with xfce4-dev-tools >= 4.17.1.

src/task-manager-bsd.c

@@ -16,6 +16,10 @@
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 #include <stdlib.h>
 #include <err.h>
 #include <sys/types.h>

src/task-manager-freebsd.c

@@ -9,6 +9,10 @@
  * (at your option) any later version.
  */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 #include <kvm.h>
 #include <sys/types.h>
 #include <sys/param.h>

src/task-manager-linux.c

@@ -8,6 +8,10 @@
  * (at your option) any later version.
  */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 #include <stdio.h>
 #include <sys/types.h>
 #include <sys/stat.h>

src/task-manager-skel.c

@@ -15,6 +15,10 @@
 #include <string.h>
 */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 #include <glib.h>
 
 #include "task-manager.h"

src/task-manager-solaris.c

@@ -8,6 +8,10 @@
  * (at your option) any later version.
  */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 #include <kstat.h>
 #include <sys/types.h>
 #include <sys/stat.h>