Revert `SendXcmOrigin` in Rococo & Westend (#2571)

Based on issue
[#2512](https://github.com/paritytech/polkadot-sdk/issues/2512), it
seems that some ecosystem teams are using these networks to set up their
staging environments and test certain use cases, some of them involving
sending XCMs from the relay with origins not allowed in the current
configuration.

This change reverts the configuration of `SendXcmOrigin`.

---------

Co-authored-by: Adrian Catangiu <adrian@parity.io>

polkadot/runtime/rococo/src/xcm_config.rs

@@ -259,11 +259,9 @@ pub type LocalPalletOriginToLocation = (
 
 impl pallet_xcm::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	// We only allow the root, fellows and the staking admin to send messages.
-	// This is basically safe to enable for everyone (safe the possibility of someone spamming the
-	// parachain if they're willing to pay the KSM to send from the Relay-chain), but it's useless
-	// until we bring in XCM v3 which will make `DescendOrigin` a bit more useful.
-	type SendXcmOrigin = xcm_builder::EnsureXcmOrigin<RuntimeOrigin, LocalPalletOriginToLocation>;
+	// Note that this configuration of `SendXcmOrigin` is different from the one present in
+	// production.
+	type SendXcmOrigin = xcm_builder::EnsureXcmOrigin<RuntimeOrigin, LocalOriginToLocation>;
 	type XcmRouter = XcmRouter;
 	// Anyone can execute XCM messages locally.
 	type ExecuteXcmOrigin = xcm_builder::EnsureXcmOrigin<RuntimeOrigin, LocalOriginToLocation>;

polkadot/runtime/westend/src/xcm_config.rs

@@ -272,7 +272,9 @@ pub type LocalPalletOriginToLocation = (
 
 impl pallet_xcm::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	type SendXcmOrigin = xcm_builder::EnsureXcmOrigin<RuntimeOrigin, LocalPalletOriginToLocation>;
+	// Note that this configuration of `SendXcmOrigin` is different from the one present in
+	// production.
+	type SendXcmOrigin = xcm_builder::EnsureXcmOrigin<RuntimeOrigin, LocalOriginToLocation>;
 	type XcmRouter = XcmRouter;
 	// Anyone can execute XCM messages locally...
 	type ExecuteXcmOrigin = xcm_builder::EnsureXcmOrigin<RuntimeOrigin, LocalOriginToLocation>;