Every build runs conf --defconfig on a copy of .config to warn if the
configuration is out of sync. This takes about a second before the
build starts.
Skip the check if the last one passed, and neither .config nor a
Kconfig file, the generated Kconfig files or conf changed since then.
If the check fails, it runs and warns again on every build, as before.
Signed-off-by: John Crispin <john@phrozen.org>
John Crispin
e7d105af30
