Comment 3 for bug 1774181

For Trusty 3.13, add the following patches:
  * UBUNTU: SAUCE: filter: Use barrier_nospec() instead of osb()
  * UBUNTU: SAUCE: Rename osb() to barrier_nospec()
  * UBUNTU: SAUCE: Replace osb() calls with array_index_nospec()
  * nospec: Kill array_index_nospec_mask_check()
  * nospec: Move array_index_nospec() parameter checking into separate macro
  * nospec: Allow index argument to have const-qualified type
  * x86/kvm: Update spectre-v1 mitigation
  * x86/spectre: Report get_user mitigation for spectre_v1
  * nl80211: Sanitize array index in parse_txq_params
  * vfs, fdtable: Prevent bounds-check bypass via speculative execution
  * x86/syscall: Sanitize syscall table de-references under speculation
  * x86/get_user: Use pointer masking to limit speculation
  * x86: Introduce barrier_nospec
  * x86: Implement array_index_mask_nospec
  * array_index_nospec: Sanitize speculative array de-references
  * Documentation: Document array_index_nospec