Revert "poky: subtree update:b23aa6b753..ad30a6d470"

This reverts commit af5e4ef732faedf66c6dc1756432e9de2ac72988.

This commit introduced openbmc/openbmc#3720 and no solution has been
forthcoming. Revert until we can get to the bottom of this.

Change-Id: I2fb0d81eb26cf3dadb2f2abdd1a1bb7a95eaf03c
diff --git a/poky/documentation/sphinx-static/theme_overrides.css b/poky/documentation/sphinx-static/theme_overrides.css
index d235cb8..55da38a 100644
--- a/poky/documentation/sphinx-static/theme_overrides.css
+++ b/poky/documentation/sphinx-static/theme_overrides.css
@@ -1,5 +1,5 @@
 /*
-    SPDX-License-Identifier: CC-BY-SA-2.0-UK
+    SPDX-License-Identifier: CC-BY-2.0-UK
 */
 
 body {