src/debug.c do not support aarch64 dump utcontext, so add the context of aarch64. The content comes from the definition of the sigcontext and tested on my aarch64 server.
src/debug.c do not support aarch64 dump utcontext, so add the context
of aarch64.
The content comes from the definition of the sigcontext and tested on
my aarch64 server.

sigcontext defined at the linux kernel code:
arch/arm64/include/uapi/asm/sigcontext.h

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