MAINTAINERS: brcm80211: remove Infineon maintainers

These email addresses no longer work, so remove them from MAINTAINERS.

Signed-off-by: Double Lo <Double.Lo@infineon.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220222015947.169224-1-double.lo@infineon.com