Eg. if only the version was changed, config.h was updated, and
everything was recompiled.
New structure, maintain these manually:
config.h.in - for configured variables that are stable if
configuration parameters are unchanged
config_version.h.in - for version/hash related variables
----
config_unused.h.in - still generated by autoheader with all
variables, don't use it
Signed-off-by: Aron Budea <aron.budea@collabora.com>
Change-Id: Id9a50a9f1e798a3b3814778d8683b7d7cb57bb29
c4975d01e5