fix: Sideloading.x failed to compile - %orig used as nested message receiver

[%orig mutableCopy] doesn't survive Logos' macro expansion cleanly (confirmed
by an actual Theos build on GitHub Actions: "error: expected identifier").
Split into two statements instead, matching how %orig is used everywhere
else in this file.

Sources/Sideloading.x

@@ -47,7 +47,8 @@ static BOOL isSelfCall(void) {
 - (NSDictionary *)infoDictionary {
     if (!isSelfCall()) return %orig;
     
-    NSMutableDictionary *info = [%orig mutableCopy];
+    NSDictionary *origInfo = %orig;
+    NSMutableDictionary *info = [origInfo mutableCopy];
     info[@"CFBundleIdentifier"] = DISCORD_BUNDLE_ID;
     info[@"CFBundleDisplayName"] = DISCORD_NAME;
     info[@"CFBundleName"] = DISCORD_NAME;