usb: renesas_usbhs: missed the "running" flag in usb_dmac with rx path

This fixes an issue that a gadget driver (usb_f_fs) is possible to
stop rx transactions after the usb-dmac is used because the following
functions missed to set/check the "running" flag.
 - usbhsf_dma_prepare_pop_with_usb_dmac()
 - usbhsf_dma_pop_done_with_usb_dmac()

So, if next transaction uses pio, the usbhsf_prepare_pop() can not
start the transaction because the "running" flag is 0.

Fixes: 8355b2b3 ("usb: renesas_usbhs: fix the behavior of some usbhs_pkt_handle")
Cc: <stable@vger.kernel.org> # v3.19+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>