usb-storage: Fix cbwflags field

SCSI layer represents DIR as TRUE or FALSE, and for SLOF TRUE is -1
and FALSE is 0, convert that to proper direction when building the
CBW

Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
usb-ohci: Convert td-phys every time to td-virt

next_td is phys pointer as well, convert that to virt

Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>