MAINTAINERS: Add entry for BD71828 charger

Add an entry for BD71828 charger driver.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Suggested-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://patch.msgid.link/20250918-bd71828-charger-v5-3-851164839c28@kemnade.info
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Author: akemnade

MAINTAINERS

@@ -22289,6 +22289,12 @@ L:	linux-serial@vger.kernel.org
 S:	Odd Fixes
 F:	drivers/tty/serial/rp2.*
 
+ROHM BD71828 CHARGER
+M:	Andreas Kemnade <andreas@kemnade.info>
+M:	Matti Vaittinen <mazziesaccount@gmail.com>
+S:	Maintained
+F:	drivers/power/supply/bd71828-charger.c
+
 ROHM BD79703 DAC
 M:	Matti Vaittinen <mazziesaccount@gmail.com>
 S:	Supported