Support collecting code coverage with wamr-test-suites script by using
lcov and genhtml tools, eg.:
cd tests/wamr-test-suites
./test_wamr.sh -s spec -b -P -C
The default code coverage and html files are generated at:
tests/wamr-test-suites/workspace/wamr.lcov
tests/wamr-test-suites/workspace/wamr-lcov.zip
And update wamr-test-suites scripts to support testing GC spec cases to
avoid frequent synchronization conflicts between branch main and dev/gc.
This syscall doesn't need allocating stack or TLS and it's expected from the application
to do that instead. E.g. WASI-libc already does this for `pthread_create`.
Also fix some of the examples to allocate memory for stack and not use stack before
the stack pointer is set to a correct value.