Bluetooth: Remove set of SrejSaveReqSeq under receipt of REJ frame

That action is not specified by the ERTM spec, so removing it.

Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>