MAINTAINERS: Add some missing directories or files

In a few cases we have MAINTAINERS entries that are missing obvious
paths or files. Typically this means a board directory that did not list
itself, but in a few cases we have a Kconfig file or similar.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/board/keymile/secu1/MAINTAINERS b/board/keymile/secu1/MAINTAINERS
index 8df25f8..e441f25 100644
--- a/board/keymile/secu1/MAINTAINERS
+++ b/board/keymile/secu1/MAINTAINERS
@@ -1,6 +1,7 @@
 Hitachi Power Grids SECU1 BOARD
 M:	Holger Brunck <holger.brunck@hitachienergy.com>
 S:	Maintained
+F:	board/keymile/secu1/
 F:	board/keymile/common/
 F:	board/keymile/scripts/
 F:	include/configs/socfpga_arria5_secu1.h