Fix IP alignment problem

This patch removes volatile from:
volatile IP_t *ip = (IP_t *)xip;

Due to a bug, avr32-gcc will assume that ip is aligned on a word boundary when
using volatile, which causes an exception since xip isn't aligned on a word
boundary.

Signed-off-by: Gunnar Rangoy <gunnar@rangoy.com>
Signed-off-by: Paul Driveklepp <pauldriveklepp@gmail.com>
Signed-off-by: Olav Morken <olavmrk@gmail.com>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>

net/net.c

@@ -1684,7 +1684,7 @@ NetSetEther(volatile uchar * xet, uchar * addr, uint prot)
 void
 NetSetIP(volatile uchar * xip, IPaddr_t dest, int dport, int sport, int len)
 {
-	volatile IP_t *ip = (IP_t *)xip;
+	IP_t *ip = (IP_t *)xip;
 
 	/*
 	 *	If the data is an odd number of bytes, zero the