[usbdev] Fix control bug on clear_rdybit
[usbdev] Fix control bug on clear_rdybit

The clear of the ready bit when a SETUP transaction completed would get
overridden by a later conditional block, which had the effect of
rewriting the logic function to never set clear_rdybit in response to
SETUP transactions.

Make the conditional blocks exclusive instead of sequential.

Signed-off-by: Stefan Lippuner <327e967db72ec2cf4c8010a51c4fcd7c9fe8c66f@iis.ee.ethz.ch>
Signed-off-by: Alexander Williams <d0fb8a15e7b6f5e62278a4cf44515038c232186c@google.com>

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