docs: boards: amlogic: add bananapi-m5 to u200 maintainer file

The bananapi-m5 docs are missing from the file, so add them.

Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20230323143142.780306-2-christianshewitt@gmail.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
diff --git a/board/amlogic/u200/MAINTAINERS b/board/amlogic/u200/MAINTAINERS
index 47cec23..919e349 100644
--- a/board/amlogic/u200/MAINTAINERS
+++ b/board/amlogic/u200/MAINTAINERS
@@ -7,4 +7,5 @@
 F:	configs/bananapi-m5_defconfig
 F:	configs/radxa-zero_defconfig
 F:	doc/board/amlogic/u200.rst
+F:	doc/board/amlogic/bananapi-m5.rst
 F:	doc/board/amlogic/radxa-zero.rst