usb: dwc3: isoc clean DWC3_EP_PENDING_REQUEST flag

After we kick_transfer we should clean
DWC3_EP_PENDING_REQUEST endpoint flag.

Signed-off-by: Janusz Dziedzic <januszx.dziedzic@linux.intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Git-commit: 87aba10639b083dacdd13b43557649b3d001c4b4
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>
Change-Id: If8528decfdb6541f414c6f0923f9fb14b5466477