[UMA] Quantized version of Vanilla example in UMA

[SamiraAFg]

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Integration of a simple custom dedicated accelerator based on Vanilla (QVanilla) into TVM using UMA to offload the QNN convolution operators.

The main changes include:

1. adding the QVanilla description to gallery/tutorial/uma.py
2. adding the QVanilla backend structure to apps/uma/qvanilla

@MichaelJKlaiber thanks in advance for your support. Please let me know if there is a problem with the context or my request.