fix a few compiler warnings in VC

zsnes/src/burn.c

@@ -91,9 +91,9 @@ void hsi2rgb(double h, double s, double i, struct colorvalue *c)
   bv = 1 + s * sin(t + 2 * M_PI / 3);
   t = 255.999 * i / 2;
   {
-    c->r = floor(rv * t);
-    c->g = floor(gv * t);
-    c->b = floor(bv * t);
+    c->r = (unsigned char) floor(rv * t);
+    c->g = (unsigned char) floor(gv * t);
+    c->b = (unsigned char) floor(bv * t);
   }
 }
 

zsnes/src/water.c

@@ -388,7 +388,7 @@ void SineBlob(int x, int y, int radius, int height, int page)
       square = cy*cy + cx*cx;
       if(square < radsquare)
       {
-        dist = sqrt(square*length);
+        dist = (int) sqrt(square*length);
         Height[page][SCRW*(cy+y) + cx+x]
           += (int)((FCos(dist)+0xffff)*(height)) >> 19;
       }