Move CTASSERT from header file to source file, per implementation note now

in the CTASSERT man page.

Submitted by:	Ryan Stone

sys/netinet/ip.h

@@ -69,10 +69,6 @@ struct ip {
 	struct	in_addr ip_src,ip_dst;	/* source and dest address */
 } __packed __aligned(4);
 
-#ifdef CTASSERT
-CTASSERT(sizeof (struct ip) == 20);
-#endif
-
 #define	IP_MAXPACKET	65535		/* maximum packet size */
 
 /*

sys/netinet/ip_input.c

@@ -85,6 +85,10 @@ __FBSDID("$FreeBSD$");
 
 #include <security/mac/mac_framework.h>
 
+#ifdef CTASSERT
+CTASSERT(sizeof(struct ip) == 20);
+#endif
+
 int rsvp_on = 0;
 
 int	ipforwarding = 0;