webos: Remove GetAllowedReferences implementation

[sundermann]

Description

This was a leftover when copying from the android implementation and is not needed on webOS. This saves some memory as the RenderManager will not allocate buffers.

Motivation and context

Cleanup some code and save some memory

How has this been tested?

LG OLED77C28LB (webOS 7/22)

What is the effect on users?

Screenshots (if appropriate):

Types of change

• Bug fix (non-breaking change which fixes an issue)
• Clean up (non-breaking change which removes non-working, unmaintained functionality)
• Improvement (non-breaking change which improves existing functionality)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that will cause existing functionality to change)
• Cosmetic change (non-breaking change that doesn't touch code)
• None of the above (please explain below)

Checklist:

• My code follows the Code Guidelines of this project
• My change requires a change to the documentation, either Doxygen or wiki
• I have updated the documentation accordingly
• I have read the Contributing document
• I have added tests to cover my change
• All new and existing tests passed