USB: dwc3: core: Set elastic buffer mode to zero

Currently elastic buffer mode in GUSB3PIPE_CTRL(0) register is
set to one. This results in high link error rates and superspeed
mode transfer failures if VDDCX is at super turbo mode voltage
1.05V. Hence set elastic buffer mode to zero in GUSB3PIP_CTRL
register.

Change-Id: Ibd5d8180202b2f877304be3da9d976fe54df3eed
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>