MAINTAINERS: Replace Siemens IPC related bouncing maintainers

Since complaints about bouncing maintainers raised [1] we have now a
replacement for maintainers that stepped away from their duties.

[1] https://www.spinics.net/lists/platform-driver-x86/msg47105.html



Signed-off-by: Benedikt Niedermayr <benedikt.niedermayr@siemens.com>
Link: https://lore.kernel.org/r/20241028112359.3333152-2-benedikt.niedermayr@siemens.com


Signed-off-by: Lee Jones <lee@kernel.org>