Keep QDQ nodes w/ nonpositive scale around MaxPool (#21182)
### Description
This change adds a check for whether the scale in the QuantizeLinear (or
DequantizeLinear) is a positive scalar, and a new selector to disallow
removing the QDQ around MaxPool if it is not.
### Motivation and Context
Currently, the DropQDQNodesRules optimization removes QuantizeLinear and
DequantizeLinear nodes from DequantizeLinear ∘ MaxPool ∘ QuantizeLinear.
However, if the x_scale/y_scale values are non-positive, the
(de-)quantization changes the ordering of the elements in the input
value, so this optimization is changing the results.
https://github.com/microsoft/onnxruntime/issues/21176
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Co-authored-by: Edward Chen <18449977+edgchen1@users.noreply.github.com>
