Upgrade LLVM to 15 when TVM build

[mshr-h]

#680
#681

[mshr-h]

The error log is here.

[100%] Building CXX object CMakeFiles/tvm_objs.dir/src/contrib/hybrid/codegen_hybrid.cc.o
[100%] Built target tvm_objs
[100%] Linking CXX shared library libtvm.dylib
ld: library not found for -lzstd
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [libtvm.dylib] Error 1
make[1]: *** [CMakeFiles/tvm.dir/all] Error 2
make: *** [all] Error 2
Error: Process completed with exit code 2.

Looks like zstd is missing but it's installed.

The same error happened on my local M1 Mac machine.
Without --link-static, the build worked fine.

CC: @masahi Have you encountered any similar errors?

[masahi]

The error is coming from LLVM. I heard that LLVM has recently started to depend on zstd. So you need to install libzstd-dev.