remove unneeded header

git-svn-id: https://geany.svn.sourceforge.net/svnroot/geany/trunk@558 ea778897-0a13-0410-b9d1-a72fbfd435f5

src/search.c

@@ -27,7 +27,6 @@
 #include "msgwindow.h"
 
 #include <unistd.h>
-#include <stdlib.h>
 
 #ifdef G_OS_UNIX
 # include <sys/types.h>