k2_fw_usb_api: workaround for EP4 bug.

This patch is workaround for xhci related issue.
After usb port resume FIFO on EP4 can't accept Bulck stream longer then
64 Bytes.
Currently we have no better way then just completly reset chip.
Side effect of this workaround - disconnection event for this device.
It means, module will be reloaded and we will get new usb minor id.
This is why, we should not do it on each firmware restart.

Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>