Queen Camilla used to be one of Kate Middleton’s “fiercest critics” — and “did object” to her marrying Prince William. King Charles’ wife believed the now-Princess of Wales, 44, was “too common” to wed William in 2011, according to Christopher Andersen’s “Kate!” biography , out last week. “She did not think she was up to snuff, as it were,” the new book reads. “She was below the salt. She had no aristocratic blood.” Queen Camilla allegedly “did object” to Kate Middleton (pictured above in November 2011) becoming Prince William’s wife. Getty Images Christopher Andersen dubbed Camilla one of the “fiercest critics” of the Princess of Wales in his new “Kate!” biography. He claimed Camilla “always saw herself as the mistress of a king, not a queen” and “picked [Princess] Diana to be Charles’ bride” in 1981. Anderson noted that “the palace didn’t really want” Middleton, whom William met attending the University of St Andrews in Scotland.…