phosphor: re-enable uninative support optionally.

Uninative support was completely removed with commit
70e685ef45a926064d27a2937d6274832c7608b4 but this is a useful
feature on systems that support it (specifically x86_64) because
it enables sstate sharing across various distribution types.
Add in the minimal support for uninative but do not enable it.
This allows someone to optionally enable it by adding the
following to a conf/local.conf:

    INHERIT += "uninative"

(From meta-phosphor rev: ea487839ed8566a43e8f9087fba850b1702f9534)

Change-Id: Ifb5ef4aee5886da676f0748c72646a1e8b775658
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/meta-phosphor/conf/distro/include/phosphor-base.inc b/meta-phosphor/conf/distro/include/phosphor-base.inc
index 7970fef..25672ef 100644
--- a/meta-phosphor/conf/distro/include/phosphor-base.inc
+++ b/meta-phosphor/conf/distro/include/phosphor-base.inc
@@ -72,6 +72,7 @@
 ERROR_QA_append = " ${WARN_TO_ERROR_QA}"
 
 require conf/distro/include/no-static-libs.inc
+require conf/distro/include/yocto-uninative.inc
 
 DISTRO = "openbmc-phosphor"
 DISTRO_NAME = "Phosphor OpenBMC (Phosphor OpenBMC Project Reference Distro)"