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/board/r360mpi/r360mpi.c b/board/r360mpi/r360mpi.c
index b502e4d..1871984 100644
--- a/board/r360mpi/r360mpi.c
+++ b/board/r360mpi/r360mpi.c
@@ -414,6 +414,6 @@
 
 U_BOOT_CMD(
 	kbd,	1,	1,	do_kbd,
-	"kbd     - read keyboard status\n",
+	"read keyboard status",
 	NULL
 );