wifi: ath11k: refactor CE remap & unmap

wifi: ath11k: refactor CE remap & unmap

Currently the logic that handles hw_params->ce_remap is inline code,
both for doing the remap and the unmap. An upcoming change needs to do
the unmap in a second place, so refactor the unmap logic into a
separate function. And although it is only called from one place,
refactor the remap logic as well to have functional symmetry.

No functional changes, compile tested only.

Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://msgid.link/20240430-ce-unmap-v1-1-e468328f95d9@quicinc.com