Some BCM6358 based boards may detect USB2.0 high speed devices as USB1.1
full speed. This is an old well known bug, but nobody cared about it. It
is quite random and hard to track.
With the latest versions of Openwrt, one user confirmed that the bug is
still there (tested router: HG556a).
Power cycle the USB PLL to fix it.
Signed-off-by: Daniel González Cabanelas <dgcbueu@gmail.com>
