[fpv/otp_ctrl] Downgrade an error to warning

This PR downgrades an error that requires top_level to declare a wire
that only used to connect two submodules.

Signed-off-by: Cindy Chen <chencindy@opentitan.org>
diff --git a/hw/formal/tools/jaspergold/jaspergold_common_message_process.tcl b/hw/formal/tools/jaspergold/jaspergold_common_message_process.tcl
index 97f557a..d49f190 100644
--- a/hw/formal/tools/jaspergold/jaspergold_common_message_process.tcl
+++ b/hw/formal/tools/jaspergold/jaspergold_common_message_process.tcl
@@ -21,6 +21,11 @@
 # Used for pwrmgr's pwrmgr_clock_enables_sva_if.sv assertion.
 set_message -warning EOBS012
 
+# Downgrade the following error to warning:
+# When two submodules are connected via a wire, there is no need to explicitly declare that wire in
+# the top module.
+set_message -warning VERI-9030
+
 # Disabling warnings:
 # We use parameter instead of localparam in packages to allow redefinition
 # at elaboration time.