usb: hub: remove redundant declarations

Fix two occurrences of the Sparse warning:

warning: symbol XXX shadows an earlier one

Signed-off-by: Kris Borer <kborer@gmail.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>