Cloning of emsdk has been accidentally removed, that caused inability to
build LLVM release with current main.
The change adds this cloning back before emsdk script is sourced.
This change is essential first step to unblock gracefully enable LLVM 21
in revive compiler as current action blindly fetched latest LLVM binary
from the list of releases on our page.
The change queries release version from the submodule and uses it. Next
step: build LLVM 21 release binary
Next next step: switch revive compile to LLVM 21 after all issues are
fixed
That's a workaround to avoid LLVM backend crash while selecting
instruction for 256-bit integer division.
The workaround needs to be removed after we switch to newest inkwell
that has a fix in RISC-V backend
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Signed-off-by: kvp <mammal_windier8j@icloud.com>
kvpanch