MAINTAINERS: wifi: ath: add Jeff Johnson as maintainer

The "ATHEROS ATH GENERIC UTILITIES" entry shares the same git tree as
the ATH10K, ATH11K, and ATH12K entries which I already maintain, so
add me to that entry as well.

Signed-off-by: Jeff Johnson <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
Link: https://patch.msgid.link/[email protected]

Author: Jeff Johnson

MAINTAINERS

@@ -3608,6 +3608,7 @@ F:	drivers/phy/qualcomm/phy-ath79-usb.c
 
 ATHEROS ATH GENERIC UTILITIES
 M:	Kalle Valo <[email protected]>
+M:	Jeff Johnson <[email protected]>
 L:	[email protected]
 S:	Supported
 F:	drivers/net/wireless/ath/*