ci: build LLVM statically

This allows `libOSMesa` to only contain the LLVM bits required instead
of shipping an entire LLVM installation.

.gitlab/ci/docker/python-osmesa/install_osmesa.sh

@@ -70,12 +70,15 @@ ls "$llvm_src"
 
 cmake -GNinja "$llvm_src/llvm" \
   -DCMAKE_BUILD_TYPE=Release \
-  -DLLVM_BUILD_LLVM_DYLIB=ON \
+  -DBUILD_SHARED_LIBS=OFF \
+  -DLLVM_BUILD_LLVM_DYLIB=OFF \
   "-DCMAKE_INSTALL_PREFIX=$llvm_prefix" \
   -DLLVM_ENABLE_RTTI=ON \
   -DLLVM_INSTALL_UTILS=ON \
   -DLLVM_ENABLE_LIBXML2=OFF \
   -DLLVM_ENABLE_BINDINGS=OFF \
+  -DBENCHMARK_ENABLE_ASSEMBLY_TEST=OFF \
+  -DLLVM_INSTALL_DOCS=OFF \
   "-DLLVM_TARGETS_TO_BUILD=$llvm_targets"
 ninja
 ninja install
@@ -103,7 +106,7 @@ meson \
   -Dshared-glapi=enabled \
   -Degl=disabled \
   -Dllvm=enabled \
-  -Dshared-llvm=enabled \
+  -Dshared-llvm=disabled \
   -Dgles1=disabled \
   -Dgles2=disabled \
   -Dglx=disabled \