make reserved spacers in microgrid regs writeable

Some registers in the VE.Bus microgrid control fields are
reserved, in case we need to add more things in future.
To make it easier, make these ranges writable so a single
write can be performed across the whole thing when required.

Author: izak

attributes.csv

@@ -132,7 +132,7 @@ com.victronenergy.vebus,/MicroGrid/DroopModeParameters/QMax/Value,d,%,208,int16,
 com.victronenergy.vebus,/MicroGrid/DroopModeParameters/UQDroop/Value,d,%,209,uint16,100,W
 com.victronenergy.vebus,/MicroGrid/DroopModeParameters/U0/Value,d,V,210,uint16,100,W
 com.victronenergy.vebus,/MicroGrid/DroopModeParameters/Activate,i,1=Send values,211,uint16,1,W
-com.victronenergy.vebus,RESERVED,d,,212,reserved[1],1,R
+com.victronenergy.vebus,RESERVED,d,,212,reserved[1],1,W
 com.victronenergy.vebus,/MicroGrid/DirectDrivePQ/Fmin,d,Hz,213,uint16,100,W
 com.victronenergy.vebus,/MicroGrid/DirectDrivePQ/Fmax,d,Hz,214,uint16,100,W
 com.victronenergy.vebus,/MicroGrid/DirectDrivePQ/P,d,%,215,int16,100,W
@@ -143,7 +143,7 @@ com.victronenergy.vebus,/MicroGrid/DirectDrivePQ/Activate,i,1=Send values,219,ui
 com.victronenergy.vebus,/MicroGrid/DirectDriveVf/F,d,Hz,220,uint16,100,W
 com.victronenergy.vebus,/MicroGrid/DirectDriveVf/U,d,V,221,uint16,100,W
 com.victronenergy.vebus,/MicroGrid/DirectDriveVf/Activate,i,1=Send values,222,uint16,1,W
-com.victronenergy.vebus,RESERVED,d,,223,reserved[7],1,R
+com.victronenergy.vebus,RESERVED,d,,223,reserved[7],1,W
 com.victronenergy.vebus,/MicroGrid/Heartbeat,i,1=Keep alive for 2 seconds,230,uint16,1,W
 com.victronenergy.vebus,/MicroGrid/Error,i,0=No Error;1=Different fallback hybrid droop parameter values between phase masters;2=Hybrid droop parameter write failed,231,uint16,1,R
 com.victronenergy.battery,/Dc/0/Power,i,W,256,int32,1,R