usb: Rename temp variable "config" to "val" in the set_avoid_reset_quirk()

In USB, the word "config" already has aseparate meaning. So it will
cause confusion if use "config" as variable's name for other purposes.
This patch is to convert the "config"  to "val"

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>