net: qrtr: Invoke sk_error_report() after setting sk_err

Rather than manually waking up any context sleeping on the sock to
signal an error we should call sk_error_report(). This has the added
benefit that in-kernel consumers can override this notification with
its own callback.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>