ath10k: Fix qmi init error handling

When ath10k_qmi_init() fails, the error handling does not free the irq
resources, which causes an issue if we EPROBE_DEFER as we'll attempt to
(re-)register irqs which are already registered.

Fix this by doing a power off since we just powered on the hardware, and
freeing the irqs as error handling.

Fixes: ba94c753 ("ath10k: add QMI message handshake for wcn3990 client")
Signed-off-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>