Fix compiler warnings in PR libsdl-org#506

Author: RobertSundling

src/SDL_ttf.c

@@ -6148,7 +6148,7 @@ bool TTF_SetFontFeatures(TTF_Font *font, char *features)
         while (*cur && *cur != ' ') cur++;
     }
 
-    font->hb_features =  SDL_calloc(sizeof(*font->hb_features), num_features);
+    font->hb_features =  SDL_calloc(num_features, sizeof(*font->hb_features));
     font->hb_features_len = num_features;
 
     char *cur = features;
@@ -6243,7 +6243,7 @@ bool TTF_SetFontVariations(TTF_Font *font, char *variations)
             font->ft_variations = (FT_Variations){0};
             return SDL_SetError("Out of memory");
         }
-        for (int i = 0; i < ft_var->num_axis; i++) {
+        for (FT_UInt i = 0; i < ft_var->num_axis; i++) {
             font->ft_variations.tags[i]     = ft_var->axis[i].tag;
             font->ft_variations.defaults[i] = ft_var->axis[i].def;
         }
@@ -6258,7 +6258,7 @@ bool TTF_SetFontVariations(TTF_Font *font, char *variations)
         while (*cur && *cur != ' ') cur++;
     }
 
-    font->hb_variations = SDL_calloc(sizeof(*font->hb_variations), num_variations);
+    font->hb_variations = SDL_calloc(num_variations, sizeof(*font->hb_variations));
     font->hb_variations_len = num_variations;
 
     char *cur = variations;