Fix 'r1' (and r2) may be used uninitialized warning in eq.cpp.

servers/audio/effects/eq.cpp

@@ -103,7 +103,9 @@ void EQ::recalculate_band_coefficients() {
 
 		//printf("band %i, precoefs = %f,%f,%f\n",i,c2a,c2b,c2c);
 
-		double r1, r2; //roots
+		// Default initializing to silence compiler warning about potential uninitialized use.
+		// Both variables are properly set in _solve_quadratic before use, or we continue if roots == 0.
+		double r1 = 0, r2 = 0; //roots
 		int roots = solve_quadratic(c2a, c2b, c2c, &r1, &r2);
 
 		ERR_CONTINUE(roots == 0);