MAINTAINERS: Add a number of "common" directories

A number of platforms have "common" directories that are in turn not
listed by the board MAINTAINERS file.  Add these directories in many
cases.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/board/keymile/kmcent2/MAINTAINERS b/board/keymile/kmcent2/MAINTAINERS
index 1426475..1026188 100644
--- a/board/keymile/kmcent2/MAINTAINERS
+++ b/board/keymile/kmcent2/MAINTAINERS
@@ -2,6 +2,8 @@
 M:	Niel Fourie <lusus@denx.de>
 S:	Maintained
 F:	board/keymile/kmcent2/
+F:	board/keymile/common/
+F:	board/keymile/scripts/
 F:	include/configs/kmcent2.h
 F:	configs/kmcent2_defconfig
 F:	arch/powerpc/dts/kmcent2.dts