USB: s3c-hsotg: Check for new request before enqueing new setup

Before trying a new setup transaction after getting an EP0 in complete
interrupt, check that the driver did not try and send more EP0 IN data
before enqueing a new setup transaction.

This fixes a bug where we cannot send all of the IN data in one go
so split the transfer, but then fail to send all the data as we start
waiting for a new OUT transaction

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>