Heading Cross Reversed (L/R)

#### Issue details
The heading indicator (circle with cross hashes) is reversed horizontally.

For example when correcting for a left-to-right crosswind, the ground track and heading indicator should be to the right of center. Currently it is left of center, and I believe that is backwards.

#### Version
1.3.56
#### Platform
[X] All
[ ] AntennaTracker
[ ] Copter
[ ] Plane
[ ] Rover
[ ] Sub

#### Airframe type
Traditional Plane

#### Hardware type
Cube autopilot and RFD900X telemetry

#### Logs
Will update if requested.

Start by reproducing the heading indicator with a left-to-right crosswind in Mission Planner 1.3.56, then trace the desktop UI code that draws the heading indicator and its ground-track correction. Done means the indicator appears to the right of center for the described correction and remains correct across the supported platforms.

Written by the indexing model from the issue text.