Add yaw in GPS fact

[Louis-max-H]

Add yaw in GPS fact and displayed it under GPS Status menu

Description

When using GPS heading along Gyroscope, QGrondControl will only show gyroscope compass, user can't know easily if heading is working correctly or what is his value. I have added yaw to gps fact and make it displayed under Vehicle GPS Status menu.

The only way before was to open MAVLink inspector and check the value of yaw. 0 will be displayed if GPS do not provide heading and N/A when heading is not available.

Test Steps

Use GPS heading,

Checklist:

• [x] Review Contribution Guidelines.
• [x] Review Code of Conduct.
• [x] I have tested my changes.

Related Issue

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