[HVM] qemu mouse: Adds support for USB mouse/tablet status check and

[HVM] qemu mouse: Adds support for USB mouse/tablet status check and
restricts Universal Host Controller interrupt generating when received
NAK in interrupt transfer.

According to usb spec, USB mouse/tablet device returns NAK to host
controller if its status does not alter in interrupt transfer.
And UHC should leave a TD active when receiving NAK and execute this
incompleted TD in a subseqent frame. UHC only generates an interrupt
on complete after the TD with ICO bit is completed.

This patch make UHC & USB mouse/tablet behave consistently with spec.

Signed-off-by: Xinmei Huang <xinmei.huang@intel.com>