Add changelog for ODL 7.16.0 and 7.17.0

[gathogojr]

Add changelog for ODL 7.16.0 and 7.17.0

[learn-build-service-prod[bot]]

Learn Build status updates of commit c4a563f:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
Odata-docs/changelog/odatalib-7x.md	:white_check_mark:Succeeded	View

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