Legend is misplaced inside a cell

* [x] I've read, understood, and done my best to follow the [*CONTRIBUTING guidelines](https://github.com/jjatie/Charts/blob/master/CONTRIBUTING.md).

## What did you do?

I'm using a LineChartView inside a cell. In awake from nib I'm applying this:
```swift
xAxis.labelPosition = .bottom
xAxis.labelFont = .boldSystemFont(ofSize: 10)
xAxis.labelTextColor = UIColor(hex: 0x6C6C6C)
xAxis.drawGridLinesEnabled = false
rightAxis.enabled = false

leftAxis.labelTextColor = UIColor(hex: 0x6C6C6C)
leftAxis.labelFont = .boldSystemFont(ofSize: 10)
leftAxis.drawAxisLineEnabled = false
leftAxis.gridColor = UIColor(hex: 0x6C6C6C)

legend.setCustom(entries: [legendEntry(title: "Values", color: style.primaryColor),
legendEntry(title: "Goal", color: style.secondaryColor),
legendEntry(title: "Goal Trend Reference", color: style.tertiaryColor)])
legend.font = .boldSystemFont(ofSize: 10)
legend.horizontalAlignment = .center
legend.textColor = UIColor(hex: 0x6C6C6C)

setVisibleXRange(minXRange: 1, maxXRange: 7)

scaleXEnabled = false
scaleYEnabled = false
pinchZoomEnabled = false
dragEnabled = false
doubleTapToZoomEnabled = false
highlightPerTapEnabled = false
highlightPerDragEnabled = false
```

## What did you expect to happen?

I expect the legend to be at the cender without overlaping one to the other.

## What happened instead?

The legend is misplaced.

## Charts Environment

**Charts version/Branch/Commit Number: 3.2.2
**Xcode version: 10.1
**Swift version: 4.2
**Platform(s) running Charts: iPhone X - 12.1
**macOS version running Xcode: Mojave

## Demo Project

No demo project, sorry