This removes USB support from the compiled kernel. Because of this, the
kernel is just small enough for the TP-Link WDR4900 to boot the
resulting kernel.
This is necessary to support the WDR4900 in the upcoming 19.xx release.
In the long run, this should be fixed with a second stage bootloader, as
the vendor bootloader only loads the first 2684k bytes.
Signed-off-by: David Bauer <mail@david-bauer.net>
84b1257f80