Command usage cleanup

Remove command name from all command "usage" fields and update
common/command.c to display "name - usage" instead of
just "usage". Also remove newlines from command usage fields.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
diff --git a/common/cmd_fdc.c b/common/cmd_fdc.c
index c6265c3..c043b97 100644
--- a/common/cmd_fdc.c
+++ b/common/cmd_fdc.c
@@ -902,7 +902,7 @@
 
 U_BOOT_CMD(
 	fdcboot,	3,	1,	do_fdcboot,
-	"fdcboot - boot from floppy device\n",
+	"boot from floppy device",
 	"loadAddr drive\n"
 );
 #endif