avoid PATH_MAX redefinition in doomtype.h (#469)

* avoid PATH_MAX redefinition in doomtype.h

Fixes #468, does it @RamonUnch ?

* move limits.h inclusion up before checking for PATH_MAX

prboom2/src/doomtype.h

@@ -61,6 +61,7 @@ typedef unsigned char byte;
 #define BETWEEN(l,u,x) ((l)>(x)?(l):(x)>(u)?(u):(x))
 #endif
 
+#include <limits.h>
 
 /* cph - Wrapper for the long long type, as Win32 used a different name.
  * Except I don't know what to test as it's compiler specific
@@ -75,14 +76,17 @@ typedef __int64 int_64_t;
 typedef unsigned __int64 uint_64_t;
 // define compiled-specific long-long contstant notation here
 #define LONGLONG(num) (uint_64_t)num
-#undef PATH_MAX
 #define strcasecmp _stricmp
 #define strncasecmp _strnicmp
 #define S_ISDIR(m)  (((m) & S_IFMT) == S_IFDIR)
 #endif
 
 #ifndef PATH_MAX
-#define PATH_MAX 1024
+  #ifdef MAX_PATH
+    #define PATH_MAX MAX_PATH
+  #else
+    #define PATH_MAX 1024
+  #endif
 #endif
 
 #ifdef __GNUC__
@@ -118,9 +122,6 @@ typedef unsigned __int64 uint_64_t;
   #define INLINE inline        /* use standard inline */
 #endif
 
-/* CPhipps - use limits.h instead of depreciated values.h */
-#include <limits.h>
-
 /* cph - move compatibility levels here so we can use them in d_server.c */
 typedef enum {
   doom_12_compatibility,   /* Doom v1.2 */