gobject-introspection: Ensure prelink config file exists to avoid build failures

gobject-introspection: Ensure prelink config file exists to avoid build failures

gobject-introspection relies upon prelink-rtld. In order to function correctly,
we generate an ld.so.conf file which is generated before users of prelink-rtld
are called.

There is currently a race in gobject-introspection since the configuration file
may not have been created. This adds in code to ensure that regardless of codepath
(new build, existing build, from sstate), we trigger the creation of the configuration
file and avoid build failures.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>