Update LLVM to v7.0.0 (bug #58689). * src/llvm.mk: Update version, checksum and download url. Update build rule. Install (native) llvm-config. * src/mingw-llvm-1-config.patch: Patch llvm-config so also the native version returns the settings that are needed for a cross build. * dist-files.mk: Add new patch to list.

#!/bin/bash
## bootstrap script
## Run this to generate the configure script

set -e      # halt if unhandled error
aclocal
autoconf    # generate configure script