Fix CC_FORCE_DISABLE=0 evaluating to true

Author: madsmtm

src/lib.rs

@@ -4158,7 +4158,7 @@ fn is_disabled() -> bool {
             // Not set? Not disabled.
             None => false,
             // Respect `CC_FORCE_DISABLE=0` and some simple synonyms.
-            Some(v) if &*v != "0" && &*v != "false" && &*v != "no" => false,
+            Some(v) if &*v == "0" || &*v == "false" || &*v == "no" => false,
             // Otherwise, we're disabled. This intentionally includes `CC_FORCE_DISABLE=""`
             Some(_) => true,
         }