eswifi: fix include path to use tls credentials

[jmasek]

Already done in 3.7 - #92242

Include path is missing when CONFIG_TLS_CREDENTIALS is set.

Fixes #92243

[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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