macOS: symbolicate arm64 crashes with `atos -arch arm64` (#3064)

The macOS crash handler hardcoded '-arch x86_64' when invoking atos
(ADDR2LINE), so backtrace symbolication produced no useful output on
Apple Silicon binaries. Select '-arch arm64' at compile time on
aarch64/arm64 targets, keeping x86_64 for Intel.

Also fix the debug log of the frame address: stackFrame.ip is a void*,
but it was printed with '0x%lx', a format/argument mismatch. Use %p.