[SCTP]: Fix unintentional change to SCTP_ASSERT when !SCTP_DEBUG

A local debugging change slipped into a previous changeset.

When SCTP_DEBUG is off SCTP_ASSERT should do nothing.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/sctp/sctp.h

@@ -255,7 +255,7 @@ extern int sctp_debug_flag;
 #define SCTP_DEBUG_PRINTK_IPADDR(whatever...)
 #define SCTP_ENABLE_DEBUG
 #define SCTP_DISABLE_DEBUG
-#define SCTP_ASSERT(expr, str, func) BUG_ON(!(expr))
+#define SCTP_ASSERT(expr, str, func)
 
 #endif /* SCTP_DEBUG */