ARM: drop unsupported 'trab' board

The 'trab' board configuration is broken, and there is nobody who is
interested and willing to fix it.  Drop it.

This includes support for VFD displays which have always been used by
this board only.

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/tools/env/fw_env.h b/tools/env/fw_env.h
index c83d608..9258c79 100644
--- a/tools/env/fw_env.h
+++ b/tools/env/fw_env.h
@@ -24,7 +24,7 @@
 /*
  * To build the utility with the run-time configuration
  * uncomment the next line.
- * See included "fw_env.config" sample file (TRAB board)
+ * See included "fw_env.config" sample file
  * for notes on configuration.
  */
 #define CONFIG_FILE     "/etc/fw_env.config"