Update included licenses iOS and Android

[louwers]

• Update "Mapbox GL uses portions of" to "MapLibre Native iOS uses portions of" / "MapLibre Native Android uses portions of"
• Rename LICENSE.mbgl-core.md to LICENSES.core.md, these are the licenses of the C/C++ dependencies of the core.
• Include licenses of core dependencies in Android and iOS LICENSE.md files.
• Run make license-check in platform/android to update versions in Android license.
• Remove SQLite blessing from iOS license. SQLite is in the public domain and does not require a license to be included.
• Remove license for Optional library (we no longer depend on this library).
• Remove Realm license (we no longer use it, it was part of the iOS build process).
• Remove mapbox-events-ios license, we no longer use it.

Closes #1520