coreos-base/update_engine: Fix opaque directory handling

When /etc way kept busy through, e.g., a process using it as CWD, then
even in the temporary namespace unmounting failed unless it was done
with the lazy option.
This pulls in flatcar/update_engine#52 to
address this.

Signed-off-by: Kai Lueke <kailuke@microsoft.com>

Author: pothos

sdk_container/src/third_party/coreos-overlay/coreos-base/update_engine/update_engine-9999.ebuild

@@ -7,7 +7,7 @@ EGIT_REPO_URI="https://github.com/flatcar/update_engine.git"
 if [[ "${PV}" == 9999 ]]; then
 	KEYWORDS="~amd64 ~arm ~arm64 ~x86"
 else
-	EGIT_COMMIT="85eea2c932a0028b90d4db2f3d495ecf73f9342a" # main
+	EGIT_COMMIT="3a44be455f7c6978e99f9e3d4f01401d80301c40" # main
 	KEYWORDS="amd64 arm64"
 fi