samples: mesh_badge: fix property ID

The mesh_badge sample uses a GATT Characteristic instead of a Mesh
Device Property to report the temperature. In addition to that the
status message is filled with with a GATT Unit instead of a the Mesh
Device Property.

Fix that by reporting a Present Device Operating Temperature, ie 0x0054
instead. This has the advantage of keeping the an s16t value to report
the temperature. This however change the marshalled format from B to A.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>