Make IFMEDIA_DEBUG a kernel option.

Sponsored by:	Nginx, Inc.

sys/conf/NOTES

@@ -2836,6 +2836,7 @@ options 	INIT_PATH=/sbin/init:/rescue/init
 options 	BUS_DEBUG	# enable newbus debugging
 options 	DEBUG_VFS_LOCKS	# enable VFS lock debugging
 options 	SOCKBUF_DEBUG	# enable sockbuf last record/mb tail checking
+options 	IFMEDIA_DEBUG	# enable debugging in net/if_media.c
 
 #
 # Verbose SYSINIT

sys/conf/options

@@ -553,6 +553,7 @@ LPT_DEBUG		opt_lpt.h
 PLIP_DEBUG		opt_plip.h
 LOCKF_DEBUG		opt_debug_lockf.h
 SI_DEBUG		opt_debug_si.h
+IFMEDIA_DEBUG		opt_ifmedia.h
 
 # Fb options
 FB_DEBUG		opt_fb.h

sys/net/if_media.c

@@ -46,6 +46,8 @@
  * to implement this interface.
  */
 
+#include "opt_ifmedia.h"
+
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/socket.h>