[NETFILTER]: nf_conntrack_sip: use strlen/strcmp

Replace sizeof/memcmp by strlen/strcmp. Use case-insensitive comparison
for SIP methods and the SIP/2.0 string, as specified in RFC 3261.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2 files changed