wcnss: Add new device interface for user control messages

wcnss userspace service will use this new control interface to configure
certain parameters required by wcnss driver. This interface is required
to configure the serial number (for MAC address auto-generation),
calibrated data availability etc. These parameters were earlier written
thru module parameters from wcnss service, however that required the
wcnss userspace daemon to have the root permission.

Change-Id: I92cc7f2c63eae08b7a467b834116883027361299
Signed-off-by: Sameer Thalappil <sameert@codeaurora.org>