scripts/genksyms: fix header usage

FreeBSD does not like <malloc.h> when __STDC__ is defined, use the standard
<stdlib.h> instead.
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>

scripts/genksyms/parse.c_shipped

@@ -160,7 +160,7 @@
 
 
 #include <assert.h>
-#include <malloc.h>
+#include <stdlib.h>
 #include "genksyms.h"
 
 static int is_typedef;

scripts/genksyms/parse.y

@@ -24,7 +24,7 @@
 %{
 
 #include <assert.h>
-#include <malloc.h>
+#include <stdlib.h>
 #include "genksyms.h"
 
 static int is_typedef;