build: move map & rng logic to their own libraries

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: I1802469f3baff4576f61accfb5a197d86a6a6964

src/utils.c

@@ -1,13 +0,0 @@
-#include "utils.h"
-
-int clamp(int value, int min, int max) {
-  if (value < min)
-    return min;
-  if (value > max)
-    return max;
-  return value;
-}
-
-int in_bounds(int x, int y, int width, int height) {
-  return x >= 0 && x < width && y >= 0 && y < height;
-}