treewide: Leverage sdbus++-gen-meson

This makes us more consistent with other projects instead of writing
meson builds for sdbus++ by hand.

Change-Id: I38b69bc67b6a3d80cda1b508a76e106a50d8ab93
Signed-off-by: Willam A. Kennington III <wak@google.com>
diff --git a/test/gen/regenerate-meson b/test/gen/regenerate-meson
new file mode 100755
index 0000000..235d551
--- /dev/null
+++ b/test/gen/regenerate-meson
@@ -0,0 +1,4 @@
+#!/bin/bash
+cd "$(dirname "$0")" || exit
+export PATH="${PWD}/../../tools:${PATH}"
+exec sdbus++-gen-meson --command meson --directory ../yaml --output .