usb: chipidea: otg: remove unnecessary B_SESS_VLD timer

Since BSV irq is enabled for B-device all the time, so B_SESS_VLD timer
is not required, and also no need to check BSV status when B_ASE0_BRST
timer timeout.

Signed-off-by: Li Jun <jun.li@freescale.com>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>