Fix validation errors about using unsupported linear filtering

[gary-sweet]

Description

Most of the samples, and parts of the framework, just build samplers using linear filtering and mipmap-modes. This is only guaranteed to be supported for a handful of formats. On my hardware this results in a large number of validation errors.

Fixes #923

General Checklist:

Please ensure the following points are checked:

• [x] My code follows the coding style
• [x] I have reviewed file licenses
• [x] I have commented any added functions (in line with Doxygen)
• [x] I have commented any code that could be hard to understand
• [x] My changes do not add any new compiler warnings
• [x] My changes do not add any new validation layer errors or warnings
• [x] I have used existing framework/helper functions where possible
• [x] My changes do not add any regressions
• [x] I have tested every sample to ensure everything runs correctly (those that run for me at least)
• [x] This PR describes the scope and expected impact of the changes I am making

Note: The Samples CI runs a number of checks including:

• [x] I have updated the header Copyright to reflect the current year (CI build will fail if Copyright is out of date)
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