qemu.inc: Always disable compile time git updating
If the SRC_URI is switched to be git based, QEMU will automatically update
itself at compile time for select git submodules. This by passes the
bitbake git fetcher. These modules are always present in the release
tarballs, so only are problematic when used with git based SRC_URIs.
These switches will have no effect on a tarball based SRC_URI.
Signed-off-by: Mark Hatle <mark.hatle@kernel.crashing.org> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
