drivers: pinctrl: remove PDC pin 198 for sdxprairie

PDC pin 198 is used by USB (gp_irq_hv[56]) and is configured in the
firmware. TLMM driver should not request a GPIO line for this pin.

Change-Id: I1641d8d364cf28d6313d92056b61f94ef03b4e3a
Signed-off-by: Lina Iyer <ilina@codeaurora.org>