Remove usbd_do_request_async. It's callback was calling usbd_free_xfer
from softint context.

Adjust callers appropriately

	- usbd_clear_endpoint_stall_async is already triggered via a
	  usb_task, so simply call usbd_do_request.

	- uhidev_set_report_async had one caller in ukbd_set_leds.
	  Convert this usage to use usb_task as well.

Discussed with mrg@
Remove the usbd_do_request_async_cb prototype. This was missed from the
previous commit.
Reset variable error to 0 before handle each ioctl cmd.  Or returns EPASSTHROUGH
when some cmds. (e.g. ODIOCGDINFO)
Get and calculate some clocks from register.
And change some dpll5 settings for DM37xx.  But I don't have it.
Tested EarthSTORM(Sliverlode) only.  EHCI works.  However clock is bad?
s/the the/the/

Bump date.