Remove duplicated return statement from llvmjit code.

The duplicated return clearly doesn't make sense / isn't
reachable. Likely introduced by me (Andres), while revising the code.

Author: Rushabh Lathia
Discussion: https://postgr.es/m/CAGPqQf2raxWOcbuTP36M1rEF3=Rfo7oD29K3psdyHMeE5swBRg@mail.gmail.com

src/backend/jit/llvm/llvmjit.c

@@ -394,7 +394,6 @@ llvm_function_reference(LLVMJitContext *context,
 		LLVMSetGlobalConstant(v_fn, true);
 
 		return LLVMBuildLoad(builder, v_fn, "");
-		return v_fn;
 	}
 
 	/* check if function already has been added */