Add visibility of the sdkinfo proto, as well as an enum for the module
to be used by SdkExtensions.
Bug: 188787081
Test: m com.android.conscrypt and inspect it
Change-Id: If8655c3328597580408a87e4c6dc4f92547a57e9
Merged-In: If8655c3328597580408a87e4c6dc4f92547a57e9
(cherry picked from commit ef9be67c2f)