fix(macos): update dependency after compiling dylib

when dellocate is used to include dependencies in python wheels, the
runtime library will have an id that is prefixed with /DLC, and that path
doesn't exist. So when generated libraries won't be able to find it
during load time. To solve this, we change the dep in the generated
library to be relative to the rpath which should be set correctly during
linking. This shouldn't have an impact when /DLC/concrete/.dylibs/* isn't
a dependecy in the first place (when not using python).

also set rpath when linking to RT lib

compiler/include/concretelang/Support/LLVMEmitFile.h

@@ -11,6 +11,8 @@ namespace concretelang {
 
 llvm::Error emitObject(llvm::Module &module, std::string objectPath);
 
+llvm::Error callCmd(std::string cmd);
+
 llvm::Error
 emitLibrary(std::vector<std::string> objectsPath, std::string libraryPath,
             std::string linker,