wcnss: Add support to download calibrated data

WCNSS Firmware needs raw NV data (settings & some register values),
to do the power-on calibration. Once firmware does the power-on
calibration; it can then re-use the calibrated data. And it need not
do the calibration again when the next time it boots. WCNSS sends this
calibrated data to Apps; and Apps saves this into a persistent area.
And in the subsequent bootup, Apps sends the calibrated data to WCNSS.

Add interfaces to read calibrated data; and also add inteface to write
calibrated data to platform driver.

Change-Id: Ic18d40150093024b10a53e28f8a423dd9d3846eb
Signed-off-by: Sameer Thalappil <sameert@codeaurora.org>