tokenring: delete last holdout of CONFIG_TR

Tokenring support was deleted in v3.5. One last holdout of the macro
CONFIG_TR escaped that fate. Until now.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 56e3e06..1dbb02c 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -144,8 +144,6 @@
 # else
 #  define LL_MAX_HEADER 96
 # endif
-#elif IS_ENABLED(CONFIG_TR)
-# define LL_MAX_HEADER 48
 #else
 # define LL_MAX_HEADER 32
 #endif