Rename SUNS_OBIS to SUNS_SINGLE_OBIS

Signed-off-by: Michael Heimpold <mhei@heimpold.de>
Add storage for dual OBIS handling

Signed-off-by: Michael Heimpold <mhei@heimpold.de>
Convert mapping of power registers to type dual obis

Signed-off-by: Michael Heimpold <mhei@heimpold.de>
Move modbus server helpers to new modbus.*

Signed-off-by: Michael Heimpold <mhei@heimpold.de>
Make compiler happy and handle this enum values

Signed-off-by: Michael Heimpold <mhei@heimpold.de>
Make stuff compilable

Signed-off-by: Michael Heimpold <mhei@heimpold.de>
Add some mapping logic

Signed-off-by: Michael Heimpold <mhei@heimpold.de>
Fix comment indentition

Signed-off-by: Michael Heimpold <mhei@heimpold.de>