Config: Remove CheckPairCurrensistency per asset random pair enabling

If all pairs aren't available, previously we'd call StorePairs and that
would leave the assetType enabled, but with nothing in pairs enabled, so
we'd turn one on randomly.

Now StorePairs will always disable assetTypes which have no enabled
pairs, so we'd always skip the end of this per-asset check.

This does not prevent the overall "At least one pair for one asset must
be turned on" logic that happens later, though I don't agree with that
either, I'm not being forced to fix it right now. Baby steps.

config/config.go

@@ -553,29 +553,7 @@ func (c *Config) CheckPairConsistency(exchName string) error {
 
 		if len(pairs) != 0 {
 			atLeastOneEnabled = true
-			continue
-		}
-
-		enabled, err := c.AssetTypeEnabled(assetTypes[x], exchName)
-		if err != nil {
-			return err
-		}
-
-		if !enabled {
-			continue
-		}
-
-		var rPair currency.Pair
-		rPair, err = availPairs.GetRandomPair()
-		if err != nil {
-			return err
-		}
-
-		err = c.SetPairs(exchName, assetTypes[x], true, currency.Pairs{rPair})
-		if err != nil {
-			return err
 		}
-		atLeastOneEnabled = true
 	}
 
 	// If no pair is enabled across the entire range of assets, then at least