Remove forward declaration for non-existent class CCoinsDB
Remove forward declaration for non-existent class CCoinsDB

Found by stephenreed on #bitcoin.dev.

(cherry picked from commit a48355dc44e8b86c2fc9f8b7973ac9e81a295be7)

reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin