sctp: fix compile error due to sysctl mismerge

I messed up the merge in d7fc02c7, where
the conflict in question wasn't just about CTL_UNNUMBERED being removed,
but the 'strategy' field is too (sysctl handling is now done through the
/proc interface, with no duplicate protocols for reading the data).

Reported-by: Larry Finger <Larry.Finger@lwfinger.net>
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>