RED RINGS OF FEAR (ENIGMA ROSSO), 1978, 85 min. Director Alberto Negrin wraps up the SOLANGE trilogy in this giallo where more sexually precocious schoolgirls bite the dust. Fabio Testi is the police inspector on the murderer’s trail, and Christine Kaufmann is his girlfriend. Chock-full of red herrings, perverse twists, sleazy situations, outrageous dialogue and an out-of-left-…