configure: Check for a sctp struct instead of just the header

This fixes build failures on debian/kfreebsd, which has the
sctp.h header, but it is currently broken (a cpp test succeeds,
but a compile test fails), see http://bugs.debian.org/684330 for
details.

Also remove the checked item from HAVE_LIST, since the corresponding
HAVE_* define isn't used by the source code.
Signed-off-by: Martin Storsjö <martin@martin.st>

configure

@@ -1153,7 +1153,6 @@ HAVE_LIST="
     mm_empty
     mmap
     nanosleep
-    netinet_sctp_h
     poll_h
     posix_memalign
     rdtsc
@@ -1605,7 +1604,7 @@ rtmpt_protocol_select="ffrtmphttp_protocol"
 rtmpte_protocol_select="ffrtmpcrypt_protocol ffrtmphttp_protocol"
 rtmpts_protocol_select="ffrtmphttp_protocol https_protocol"
 rtp_protocol_select="udp_protocol"
-sctp_protocol_deps="network netinet_sctp_h"
+sctp_protocol_deps="network struct_sctp_event_subscribe"
 tcp_protocol_deps="network"
 tls_protocol_deps_any="openssl gnutls"
 tls_protocol_select="tcp_protocol"
@@ -2979,7 +2978,7 @@ if enabled network; then
     check_type poll.h "struct pollfd"
     check_type "sys/types.h sys/socket.h" "struct sockaddr_storage"
     check_struct "sys/types.h sys/socket.h" "struct sockaddr" sa_len
-    check_header netinet/sctp.h
+    check_type netinet/sctp.h "struct sctp_event_subscribe"
     check_func getaddrinfo $network_extralibs
     # Prefer arpa/inet.h over winsock2
     if check_header arpa/inet.h ; then