ath10k: add spectral scan support for 10.4 fw

To enable/configure spectral scan parameters in 10.4 firmware, existing
wmi spectral related functions can be reused. Link those functions in
10.4 wmi ops table.

In addition, adjust bin size (only when size is 68 bytes) before reporting
bin samples to user space. The background for this adjustment is that
qca99x0 reports bin size as 68 bytes (64 bytes + 4 bytes) in report
mode 2. First 64 bytes carries in-band tones (-32 to +31) and last 4 byte
carries band edge detection data (+32) mainly used in radar detection
purpose. Additional last 4 bytes are stripped to make bin size valid one.

This bin size adjustment will happen only for qca99x0, all other chipsets
will report proper bin sizes (64/128) without extra 4 bytes being added
at the end. The changes are validated in qca99x0 using 10.4 firmware.

Signed-off-by: Raja Mani <rmani@qti.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>