Update to LLVM 12.0

Author: light-tech

build-llvm-framework.sh

@@ -13,7 +13,7 @@ wget https://github.com/ninja-build/ninja/releases/download/v1.10.2/ninja-mac.zi
 unzip ninja-mac.zip
 
 git clone https://github.com/libffi/libffi.git
-git clone --single-branch --branch release/11.x https://github.com/llvm/llvm-project.git
+git clone --single-branch --branch release/12.x https://github.com/llvm/llvm-project.git
 
 FRAMEWORKS_ARGS=()
 for p in ${PLATFORMS[@]}; do