Improve and of ICMP messages on Windows.

When an ICMP message is received on Windows 10 for a UDP socket,
WSAECONNRESET is reported as an error. In this case, just read
again.

Thanks to nxrighthere for reporting the issue and helping to
nail it down.

This fixes #309.
diff --git a/usrsctplib/user_recv_thread.c b/usrsctplib/user_recv_thread.c
index 3428806..4d73a31 100755
--- a/usrsctplib/user_recv_thread.c
+++ b/usrsctplib/user_recv_thread.c
@@ -323,12 +323,10 @@
 		nResult = WSARecvFrom(SCTP_BASE_VAR(userspace_rawsctp), recv_iovec, MAXLEN_MBUF_CHAIN, &ncounter, &flags, (struct sockaddr *)&from, &fromlen, NULL, NULL);
 		if (nResult != 0) {
 			m_ErrorCode = WSAGetLastError();
-			if (m_ErrorCode == WSAETIMEDOUT) {
-				continue;
-			}
 			if ((m_ErrorCode == WSAENOTSOCK) || (m_ErrorCode == WSAEINTR)) {
 				break;
 			}
+			continue;
 		}
 		n = ncounter;
 #else
@@ -516,10 +514,10 @@
 		}
 		if (nResult != 0) {
 			m_ErrorCode = WSAGetLastError();
-			if (m_ErrorCode == WSAETIMEDOUT)
-				continue;
-			if (m_ErrorCode == WSAENOTSOCK || m_ErrorCode == WSAEINTR)
+			if ((m_ErrorCode == WSAENOTSOCK) || (m_ErrorCode == WSAEINTR)) {
 				break;
+			}
+			continue;
 		}
 		n = ncounter;
 #else
@@ -728,12 +726,10 @@
 		}
 		if (nResult != 0) {
 			m_ErrorCode = WSAGetLastError();
-			if (m_ErrorCode == WSAETIMEDOUT) {
-				continue;
-			}
 			if ((m_ErrorCode == WSAENOTSOCK) || (m_ErrorCode == WSAEINTR)) {
 				break;
 			}
+			continue;
 		}
 		n = ncounter;
 #endif
@@ -935,12 +931,10 @@
 		}
 		if (nResult != 0) {
 			m_ErrorCode = WSAGetLastError();
-			if (m_ErrorCode == WSAETIMEDOUT) {
-				continue;
-			}
 			if ((m_ErrorCode == WSAENOTSOCK) || (m_ErrorCode == WSAEINTR)) {
 				break;
 			}
+			continue;
 		}
 		n = ncounter;
 #endif