parser: find SIZE_MAX on older versions of glibc and g++

Another issue with commit 2456 is that with older versions of glibc and
g++, a definition for SIZE_MAX was not being found; e.g. on Ubuntu 12.04
LTS and 12.10, the parser fails to compile with the following error:

  g++ -g -O2 -pipe -Wall -Wsign-compare -Wmissing-field-initializers -Wformat-security -Wunused-parameter -std=gnu++0x -D_GNU_SOURCE -DPACKAGE=\"apparmor-parser\" -DLOCALEDIR=\"/usr/share/locale\" -DSUBDOMAIN_CONFDIR=\"/etc/apparmor\" -I../libraries/libapparmor//include -c -o lib.o lib.c
  lib.c: In function 'int str_escseq(const char**, const char*)':
  lib.c:292:32: error: 'SIZE_MAX' was not declared in this scope

The following patch addresses the issue by explicitly including the C stdint
header which contains the definition for SIZE_MAX.

Signed-off-by: Steve Beattie <steve@nxnw.org>
Acked-by: John Johansen <john.johansen@canonical.com>

parser/lib.c

@@ -29,6 +29,8 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
+#include <cstdint>
+
 #include "lib.h"
 #include "parser.h"