rndis_host: increase sleep time in the query-response loop

Some WinCE devices face connectivity issues via the NDIS interface. They
fail to register, resulting in -110 timeout errors and failures during the
probe procedure.

In this kind of WinCE devices, the Windows-side ndis driver needs quite
more time to be loaded and configured, so that the linux rndis host queries
to them fail to be responded correctly on time.

More specifically, when INIT is called on the WinCE side - no other
requests can be served by the Client and this results in a failed QUERY
afterwards.

The increase of the waiting time on the side of the linux rndis host in
the command-response loop leaves the INIT process to complete and respond
to a QUERY, which comes afterwards. The WinCE devices with this special
"feature" in their ndis driver are satisfied by this fix.

Signed-off-by: Olympia Giannou <olympia.giannou@leica-geosystems.com>
Signed-off-by: David S. Miller <davem@davemloft.net>