usb/phy: fix PPC64 build errors in phy-fsl-usb.c

usb/phy: fix PPC64 build errors in phy-fsl-usb.c

Fix build errors when built for PPC64:
These variables are only used on PPC32 so they don't need to be
initialized for PPC64.

../drivers/usb/phy/phy-fsl-usb.c: In function 'usb_otg_start':
../drivers/usb/phy/phy-fsl-usb.c:865:3: error: '_fsl_readl' undeclared (first use in this function); did you mean 'fsl_readl'?
   _fsl_readl = _fsl_readl_be;
../drivers/usb/phy/phy-fsl-usb.c:865:16: error: '_fsl_readl_be' undeclared (first use in this function); did you mean 'fsl_readl'?
   _fsl_readl = _fsl_readl_be;
../drivers/usb/phy/phy-fsl-usb.c:866:3: error: '_fsl_writel' undeclared (first use in this function); did you mean 'fsl_writel'?
   _fsl_writel = _fsl_writel_be;
../drivers/usb/phy/phy-fsl-usb.c:866:17: error: '_fsl_writel_be' undeclared (first use in this function); did you mean 'fsl_writel'?
   _fsl_writel = _fsl_writel_be;
../drivers/usb/phy/phy-fsl-usb.c:868:16: error: '_fsl_readl_le' undeclared (first use in this function); did you mean 'fsl_readl'?
   _fsl_readl = _fsl_readl_le;
../drivers/usb/phy/phy-fsl-usb.c:869:17: error: '_fsl_writel_le' undeclared (first use in this function); did you mean 'fsl_writel'?
   _fsl_writel = _fsl_writel_le;

and the sysfs "show" function return type should be ssize_t, not int:

../drivers/usb/phy/phy-fsl-usb.c:1042:49: error: initialization of 'ssize_t (*)(struct device *, struct device_attribute *, char *)' {aka 'long int (*)(struct device *, struct device_attribute *, char *)'} from incompatible pointer type 'int (*)(struct device *, struct device_attribute *, char *)' [-Werror=incompatible-pointer-types]
 static DEVICE_ATTR(fsl_usb2_otg_state, S_IRUGO, show_fsl_usb2_otg_state, NULL);

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: linux-usb@vger.kernel.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>