ath11k: use hw_params to access board_size and cal_offset

Reuse board_size from hw_params, add cal_offset to hw params.
This patch is clean up only, there is no change in functionality.

cal_size was unused, so remove that.

Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.4.0.1-00009-QCAHKSWPL_SILICONZ-1
Tested-on: QCN9074 hw1.0 PCI WLAN.HK.2.4.0.1-01838-QCAHKSWPL_SILICONZ-1

Signed-off-by: Anilkumar Kolli <akolli@codeaurora.org>
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210721201927.100369-2-jouni@codeaurora.org