Make clear that qcaspi_qca7k_sync() handles a fsm by using switch

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
After the spi thread is running, the packet queueing can be started

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
First stop queueing packets in qcaspi_netdev_close()

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
GFP_KERNEL should suffice in ndo_init()

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reduce the indentation and refuse probing if there are no Device
Tree

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>