Fix EFA interface count for instances where MaximumNetworkCards exceeds EFA limit

[kprahulraj]

Description

Fixes #8685

We tried to set EFA's by using MaximumNetworkCards. This worked for all previous EFA-capable instances in cases where MaximumEfaInterfaces = MaximumNetworkCards, but starts to break in the latest instance types.

To fix this using NetworkInfo.EfaInfo.MaximumEfaInterfaces to determine the EFA interface count, with fallback to MaximumNetworkCards when EfaInfo is not populated.

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the userdocs directory)
• Manually tested
• Made sure the title of the PR is a good description that can go into the release notes
• (Core team) Added labels for change area (e.g. area/nodegroup) and kind (e.g. kind/improvement)

BONUS POINTS checklist: complete for good vibes and maybe prizes?! 🤯

• Backfilled missing tests for code in same general area 🎉
• Refactored something and made the world a better place 🌟