glibc: set ld.so.conf as conf file

This enables simple overwriting when multilib is in use.

(From OE-Core rev: 52e57a13f874cf4093682c9d9463e9b964f6de17)

Signed-off-by: Benjamin Bara <benjamin.bara@skidata.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/glibc/glibc-package.inc

@@ -26,6 +26,7 @@ INSANE_SKIP:${PN}-dev += "staticdev"
 INSANE_SKIP:${MLPREFIX}ldso:append = " dev-so libdir"
 
 FILES:${PN} = "${libc_baselibs} ${libexecdir}/* ${sysconfdir}/ld.so.conf"
+CONFFILES:${PN} = "${sysconfdir}/ld.so.conf"
 RRECOMMENDS:${PN} = "${@bb.utils.contains('DISTRO_FEATURES', 'ldconfig', '${MLPREFIX}ldconfig', '', d)}"
 FILES:ldconfig = "${base_sbindir}/ldconfig"
 FILES:ldd = "${bindir}/ldd"