DRA: Add MatchExpression constraint support for devices

[geetasg]

Enhancement Description

DRA supports specifying constraints for device allocation. Currently, it supports the MatchAttribute constraint, which ensures that all selected devices have a specific attribute and that the type and value of this attribute are consistent across these devices. This enhancement proposal aims to add a new MatchExpression constraint that will allow devices to be evaluated against a CEL expression. For example - consider an accelerator architecture where connected devices have sequential identifiers. A MatchExpression constraint can help select a subset of these connected devices. This feature was previously identified as a potential future extension in the original KEP for structured parameters, and this proposal seeks to implement that extension.
Ref: - https://github.com/kubernetes/enhancements/blame/master/keps/sig-node/4381-dra-structured-parameters/README.md#L1597

• One-line enhancement description (can be used as a release note): Provide a mechanism which compares different devices and returns true if they qualify as an optimal set.
• Kubernetes Enhancement Proposal: TBD
• Discussion Link: Discussed in community meeting on 4/15/2025
• Primary contact (assignee): geetasg
• Responsible SIGs:
• Enhancement target (which target equals to which milestone):
  • Alpha release target (x.y): 1.34
  • Beta release target (x.y):
  • Stable release target (x.y):
• Alpha
  • KEP (k/enhancements) update PR(s):
  • Code (k/k) update PR(s):
  • Docs (k/website) update PR(s):

Please keep this description up to date. This will help the Enhancement Team to track the evolution of the enhancement efficiently.

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[geetasg]

cc @pohly @dims