shop_ship.php: replace explicit query with methods
shop_ship.php: replace explicit query with methods

Use the `SmrLocation::getShipsSold` method instead of explicitly
duplicating the query here.

hemberger/smr,smrealms/smr,smrealms/smr,hemberger/smr,hemberger/smr,smrealms/smr,hemberger/smr