meta-qt5: update layer

Update to latest content in Qt 5.12.1 branch.

Task-number: QTBUG-72255
Change-Id: I2d6d4a434047ba9e7234287cb4738c3189eeb1f5
Reviewed-by: Samuli Piippo <samuli.piippo@qt.io>

scripts/manifest.xml

@@ -26,7 +26,7 @@
            path="sources/meta-openembedded"/>
   <project name="meta-qt5"
            remote="qtyocto"
-           revision="0f27849166952e5ca377084a0746182169eaf324"
+           revision="b9131d61d3f08669b493b5070811f2c617c8ee9f"
            path="sources/meta-qt5"/>
   <project name="meta-mingw"
            remote="qtyocto"