Add missing algorithm include to some files

Fix missing std::clamp

src/hwr2/twodee_renderer.cpp

@@ -10,6 +10,7 @@
 
 #include "twodee_renderer.hpp"
 
+#include <algorithm>
 #include <unordered_set>
 
 #include <stb_rect_pack.h>

src/r_draw.cpp

@@ -16,6 +16,8 @@
 ///        not the architecture of the frame buffer.
 ///        The frame buffer is a linear one, and we need only the base address.
 
+#include <algorithm>
+
 #include "doomdef.h"
 #include "doomstat.h"
 #include "r_local.h"