x86 stub support

[dylonChime]

ℹ️ Description

Add support for X86 stub. Note this is a non-functional x86 stub. We do not currently support x86 architectures.

Type of change

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [x] This change requires a documentation update
  • [x] README update
  • [x] CHANGELOG update
  • [ ] guides update
• [x] This change requires a dependency update
  • [x] Amazon Chime SDK Media
  • [ ] Other (update corresponding legal documents)

🧪 How Has This Been Tested?

Demo sanity testing and file structure was verified for SDK aar and demo APK.

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