usb: otg: Add workaround for PNOC performance issue

PNOC (Peripheral NOC) present on some MSM targets has
a hardware BUG which degrades the USB peripheral performance.
Fix this by adding a software workaround that changes the
USB mem-type attribute value (from 0 to 2) via VMIDMT.

Change-Id: I2249f1aa81c457032c6f8818f5c5d3820bea66d3
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>