dsmr: also migrate entries for devices with correct serial
When the dsmr code could not find the serial_nr for the gas meter,
it creates the gas meter device with the entry_id as identifier.
But when there is a correct serial_nr, it will use that as identifier
for the dsmr gas device.
Now the migration code did not take this into account, so migration to
the new name failed since it didn't look for the device with correct
serial_nr.
This commit fixes this and adds a test for this.
* Add support for multiple mbus devices in dsmr
A dsmr meter can have 4 mbus devices.
Support them all and also add support for a water meter on the mbus
device.
* Apply suggestions from code review
Co-authored-by: Jan Bouwhuis <jbouwh@users.noreply.github.com>
* Rewrite old gas sensor to new mbus sensor
* No force updates + fix mbus entity unique_id
* Remove old gas device
* Add additional tests
* Fix remarks from last review + move migrated 5b gas meter to new device_id
* Fix ruff error
* Last fixes
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Co-authored-by: Jan Bouwhuis <jbouwh@users.noreply.github.com>