habanalabs: add opcode to INFO IOCTL to return clock rate

Add a new opcode to the INFO IOCTL to allow the user application to
retrieve the ASIC's current and maximum clock rate. The rate is
returned in MHz.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Reviewed-by: Tomer Tayar <ttayar@habana.ai>