i#3544 RV64: Port more sample tests to RISC-V

[ksco]

Ports sample.opcodes and sample.callstack tests to RISC-V.

Unlike other architectures, there are no control flags in RISC-V, we use common.hello as the application to run sample tests, sample.callstack.control_flags.templatex is renamed to sample.callstack.templatex.

sample.callstack is yet another test that does not run on QEMU.

Issue: #3544

[ksco]

I noticed sample.callstack test passed on my local x86_64 dev machine with QEMU v7.1.0, but failed in CI, so I took a look on the CI env. using tmate:

runner@fv-az1427-290:~/work/dynamorio/dynamorio/build_riscv64-debug-internal$ qemu-riscv64 --version
qemu-riscv64 version 6.2.0 (Debian 1:6.2+dfsg-2ubuntu6.18)
Copyright (c) 2003-2021 Fabrice Bellard and the QEMU Project developers
runner@fv-az1427-290:~/work/dynamorio/dynamorio/build_riscv64-debug-internal$ qemu-riscv64 -L /usr/riscv64-linux-gnu bin64/drrun -debug -xarch_root /usr/riscv64-linux-gnu -stderr_mask 0xC -c api/bin/libcallstack.so -- suite/tests/bin/common.hello
wrapping /usr/riscv64-linux-gnu/lib/libc.so.6!malloc
malloc called from:
Segmentation fault (core dumped)
runner@fv-az1427-290:~/work/dynamorio/dynamorio/build_riscv64-debug-internal$

Maybe this is simply because QEMU is too old? Will try to upgrade QEMU in future PR to enable more tests.