USB: dwc3: gadget: Reset device core before setting Run/stop bit

When cable is disconnected, SW does device initiated disconnect
by clearing run/stop bit in DCTL register. When software wants to
reconnect to host, it has to do soft reset USB core and then
do device reinitialization.

By default max burst size for for control endpoints are initialized
to zero. This leads to setting burst size to non zero value for
control endpoints as part of reenabling endpoint 0 and 1 which results
in command queued for ep0 out getting timed out. Hence fix this by
initializing burst size to one in udc_start() API.

CRs-Fixed: 494807
Change-Id: I0a23ae8bc80932f9f66f792a1149ad5d8ac7d4a2
Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>