CPP: remove old deprecated predicate that was recently updated by an automated patch of mine

Author: erik-krogh

cpp/ql/lib/semmle/code/cpp/commons/Printf.qll

@@ -408,13 +408,6 @@ class FormatLiteral extends Literal {
    */
   FormattingFunctionCall getUse() { result.getFormat() = this }
 
-  /**
-   * Holds if the default meaning of `%s` is a `wchar_t *`, rather than
-   * a `char *` (either way, `%S` will have the opposite meaning).
-   * DEPRECATED: Use getDefaultCharType() instead.
-   */
-  deprecated predicate isWideCharDefault() { this.getUse().getTarget().isWideCharDefault() }
-
   /**
    * Gets the default character type expected for `%s` by this format literal.  Typically
    * `char` or `wchar_t`.