Fix the following build warnings on x86:

drivers/usb/chipidea/core.c: In function 'hw_phymode_configure':
drivers/usb/chipidea/core.c:226:3: warning: large integer implicitly truncated to unsigned type [-Woverflow]
drivers/usb/chipidea/core.c:230:3: warning: large integer implicitly truncated to unsigned type [-Woverflow]
drivers/usb/chipidea/core.c:243:3: warning: large integer implicitly truncated to unsigned type [-Woverflow]
drivers/usb/chipidea/core.c:246:3: warning: large integer implicitly truncated to unsigned type [-Woverflow]
Reported-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>