test: Extend depserv test with per-service reload, fix slay race

Verify that 'initctl reload foo' properly triggers dependent
services by checking that bar gets a new PID after the reload.
Also change the second test case from service/foo/running to
service/foo/ready which is the actual condition set by pidfile.so.

Fix a race in slay where the target process could exit between
the PID lookup and kill -9, causing spurious test failures in
tight kill loops (e.g., start-kill-service.sh).

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

test/src/serv.c

@@ -325,6 +325,12 @@ int main(int argc, char *argv[])
 #endif
 				}
 			}
+
+			if (melange) {
+				mine(melange);
+				vanish = -2;
+			}
+
 			if (do_pidfile > 0)
 				pidfile(NULL);
 			reloading = 0;