external/boringssl: Sync to aa2485.

This includes the following changes:

https://boringssl.googlesource.com/boringssl/+log/171b5403ee767fa0f3aecd377867db6533c3eb8f..aa24851515d6280aa1d6a8b1548fe74691df3136

Bug: 29744850
Change-Id: Id4e4a9e7a19c2f0badbaead2c39a51037ba182ed
292 files changed