[NET]: Use NIP6_FMT in kernel.h

There are errors and inconsistency in the display of NIP6 strings.
	ie: net/ipv6/ip6_flowlabel.c

There are errors and inconsistency in the display of NIPQUAD strings too.
	ie: net/netfilter/nf_conntrack_ftp.c

This patch:
	adds NIP6_FMT to kernel.h
	changes all code to use NIP6_FMT
	fixes net/ipv6/ip6_flowlabel.c
	adds NIPQUAD_FMT to kernel.h
	fixes net/netfilter/nf_conntrack_ftp.c
	changes a few uses of "%u.%u.%u.%u" to NIPQUAD_FMT for symmetry to NIP6_FMT

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index e6ee2d9..323924e 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -216,6 +216,7 @@
 	((unsigned char *)&addr)[1], \
 	((unsigned char *)&addr)[2], \
 	((unsigned char *)&addr)[3]
+#define NIPQUAD_FMT "%u.%u.%u.%u"
 
 #define NIP6(addr) \
 	ntohs((addr).s6_addr16[0]), \
@@ -226,6 +227,7 @@
 	ntohs((addr).s6_addr16[5]), \
 	ntohs((addr).s6_addr16[6]), \
 	ntohs((addr).s6_addr16[7])
+#define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
 
 #if defined(__LITTLE_ENDIAN)
 #define HIPQUAD(addr) \