[iOS/tvOS] Enable RSA operations

[MaximLipnin]

There is a set of the native RSA encrypt/decrypt operations which were disabled on iOS/tvOS in #33970 since most of them depend on the types/methods from the security framework, which are mostly available on MacOSX and seem not to have ready-to-use analogs for iOS/tvOS.

During the work for annotating any unavailable APIs as unsupported, all managed calls into those RSA operations lead to the analyzer warnings. I've tried to re-enable the native part but it seems to be more time consuming/requiring more experience in the security area so the plan is to add the warning suppressions for now.

Part of #47910

@steveisok @akoeplinger

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Issue Details

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There is a set of the native RSA encrypt/decrypt operations which were disabled on iOS/tvOS in #33970 since most of them depend on the types/methods from the security framework, which are mostly available on MacOSX and seem not to have ready-to-use analogs for iOS/tvOS.

During the work for annotating any unavailable APIs as unsupported, all managed calls into those RSA operations lead to the analyzer warnings. I've tried to re-enable the native part but it seems to be more time consuming/requiring more experience in the security area so the plan is to add the warning suppressions for now.

@steveisok @akoeplinger

Author:	MaximLipnin
Assignees:	-
Labels:	area-System.Security
Milestone:	-

[MaximLipnin]

@filipnavara Taking into account the recent changes you've made in #51620, can we close this issue as resolved?

[filipnavara]

Yes. This can be closed now.