[runtimes][NFC] Consistently declare main() functions in tests (#162548)
In the libc++ test suite, we consistently declare main() functions with
full parameters and explicitly return from the function. This helps code
that compiles the tests with -ffreestanding, where main() is not a
special function (with an implicit return and special mangling).
This patch fixes a few stray declarations, including in libunwind and
libc++abi.
GitOrigin-RevId: 4f80c064eb2933c00c0ba9b7826aa3631cf3b5c2
2 files changed
