Remove the includes of <sys/types.h> and <sys/wait.h> from *.c

These are included from spawn.h under Unix now.
Also fixes spawn.c including <sys/wait.h> without <sys/types.h>

src/search.c

@@ -50,11 +50,6 @@
 #include <string.h>
 #include <ctype.h>
 
-#ifdef G_OS_UNIX
-# include <sys/types.h>
-# include <sys/wait.h>
-#endif
-
 #include <gdk/gdkkeysyms.h>
 
 enum

src/spawn.c

@@ -1068,9 +1068,6 @@ gboolean spawn_sync(const gchar *working_directory, const gchar *command_line, g
 /* tests, not part of the API */
 #ifdef SPAWN_TEST
 #include <stdio.h>
-#ifndef WIFEXITED
-#include <sys/wait.h>  /* WIFEXITED */
-#endif
 
 
 static gboolean read_line(const char *prompt, char *buffer, size_t size)

src/tools.c

@@ -46,11 +46,6 @@
 #include <string.h>
 #include <errno.h>
 
-#ifdef G_OS_UNIX
-# include <sys/types.h>
-# include <sys/wait.h>
-#endif
-
 
 enum
 {