upstream: Remove unused ssh_packet_start_compression()

ok markus@

OpenBSD-Commit-ID: 9d34cf2f59aca5422021ae2857190578187dc2b4
diff --git a/opacket.h b/opacket.h
index b2c2e7f..f92fe58 100644
--- a/opacket.h
+++ b/opacket.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: opacket.h,v 1.12 2017/10/20 01:56:39 djm Exp $ */
+/* $OpenBSD: opacket.h,v 1.13 2018/07/06 09:03:02 sf Exp $ */
 #ifndef _OPACKET_H
 /* Written by Markus Friedl. Placed in the public domain.  */
 
@@ -59,8 +59,6 @@
 	ssh_packet_set_protocol_flags(active_state, (protocol_flags))
 #define packet_get_protocol_flags() \
 	ssh_packet_get_protocol_flags(active_state)
-#define packet_start_compression(level) \
-	ssh_packet_start_compression(active_state, (level))
 #define packet_start(type) \
 	ssh_packet_start(active_state, (type))
 #define packet_put_char(value) \