USB: storage: fix compile warning
USB: storage: fix compile warning

This patch should fix the below compile warning:

drivers/usb/storage/protocol.c: In function 'usb_stor_access_xfer_buf':
drivers/usb/storage/protocol.c:155:22: warning: comparison of distinct
pointer types lacks a cast [enabled by default]

Reported-by: kbuild test robot <24f7fe9d205c8a9f6ade0c2894e14303ca16087f@intel.com>
Reported-by: Stephen Rothwell <4bf0fb350827ce8d86875e76c923a478597c3cef@canb.auug.org.au>
Signed-off-by: Ming Lei <8d0fc11caeb4659419f0ba3104eb4a9d30848d42@canonical.com>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs