toml: be less stringent on 'debug' profile, we already emit a warning on it

Author: da-x

src/cargo/util/toml/mod.rs

@@ -536,9 +536,16 @@ impl TomlProfile {
         }
 
         match name {
-            "package" | "build" | "debug" => {
+            "package" | "build" => {
                 failure::bail!("Invalid {}: `{}`", what, name);
             }
+            "debug" if what == "profile" => {
+                if what == "profile name" {
+                    // Allowed, but will emit warnings
+                } else {
+                    failure::bail!("Invalid {}: `{}`", what, name);
+                }
+            }
             "doc" if what == "dir-name" => {
                 failure::bail!("Invalid {}: `{}`", what, name);
             }