protobuf

Merge pull request #8948 from compnerd/split-check

Fix unreachable code return in a case label that has a switch with only a default case in it, which returns already (#8927)

build: fix the support for CMake[<3.7]

Merge pull request #8944 from jtattermusch/fix_arm64_dockcross_break

fix arm64 C++ tests broken by dockcross image update