kcsbridge: Add alternative daemon

This removes the unused signal handling logic and ensures that the main
event loop only drives timeouts from the management channel, and
transitions back to reading when needed.

Change-Id: I01a70de8b301b5ba0b417922fd6a6555433e18b7
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/subprojects/sdeventplus.wrap b/subprojects/sdeventplus.wrap
new file mode 100644
index 0000000..7503664
--- /dev/null
+++ b/subprojects/sdeventplus.wrap
@@ -0,0 +1,3 @@
+[wrap-git]
+url = https://github.com/openbmc/sdeventplus
+revision = HEAD