qtnfmac: use MAJOR.MINOR format for firmware protocol

Use MAJOR.MINOR format for QLink firmware protocol. MAJOR part is
incremented when backward compatibility is broken. Normally this
part should not be incremented unless there is a good reason for
that. MINOR part is incremented each time when new features are
added to qlink.h, e.g. new TLVs, events, commands. These changes
should not break backward compatibility. For instance, older
firmware versions may not be able to parse new flags or send new
types of events, but this does not impact normal system operations.

As part of initialization sequence, driver requests protocol version
from firmware and refuses to start in case there is a mismatch in MAJOR
part of the version.

Signed-off-by: Igor Mitsyanko <igor.mitsyanko.os@quantenna.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>