Before she showed Pop paintings at the Whitney and the Guggenheim; before her madcap plays were performed at the Judson Poets’ Theater and La MaMa; before she traveled the female wrestling circuit as Rosa Carlo, the Mexican Spitfire — before all that, Rosalyn Drexler was Rosalind Bronznick, a Jewish girl from the Bronx with a wimple of sprayed hair. In her teens, she studied piano and voice because her family wanted her to be a star like her uncle Chico Marx, but she never made it to Hollywood. Instead, she had walk-on parts in “Midtown hotels where distant relatives and…