ath11k: Introduce spectral hw configurable param

Below parameters have been identified as configurable across the platforms.
So to scale the spectral across the platforms, move these parameter
into hw param.

	1. Maximum FFT bins
	2. Summary report pad size
	3. FFT report header length

Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.4.0.1-01492-QCAHKSWPL_SILICONZ-1
Tested-on: IPQ6018 hw1.0 AHB WLAN.HK.2.4.0.1-00330-QCAHKSWPL_SILICONZ-1

Signed-off-by: Karthikeyan Periyasamy <periyasa@codeaurora.org>
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210721180809.90960-3-jouni@codeaurora.org