Fix access to files with long file names on win32/win64

Long path were already handled with a prefix '\\?\' thanks to ALLOC_WIN32_PATH macro defined in platforms/win32/plugins/FilePlugin/sqWin32File.h
Unfortunately, when concatenating a file path shorter than MAX_PATH with a file name making the total longer than MAX_PATH,
using the macro REALLOC_WIN32_PATH, there were no '\\?\' prepended, and the file access did fail...

This commit does fix the REALLOC_WIN32_PATH to handle the case when path become longer than limit after growth.

platforms/win32/plugins/FilePlugin/sqWin32File.h

@@ -48,13 +48,20 @@
 
 //  if(wcscpy_s(in_out_wide_path, in_size < sz ? in_size : sz, tmp) != 0) FAIL(); \
 
-#define REALLOC_WIN32_PATH(in_out_wide_path, in_size) { \
+#define REALLOC_WIN32_PATH(in_out_wide_path, in_out_size) { \
   int sz = wcslen(in_out_wide_path); \
   WCHAR *tmp = in_out_wide_path; \
-  in_out_wide_path = (WCHAR*)alloca((in_size+1) * sizeof(WCHAR)); \
-  if(in_size < sz) tmp[in_size] = 0; \
-  wcscpy(in_out_wide_path, tmp); \
-  in_out_wide_path[in_size] = 0; \
+  in_out_wide_path = (WCHAR*)alloca((in_out_size+1) * sizeof(WCHAR)); \
+  if(in_out_size < sz) tmp[in_out_size] = 0; \
+  if(in_out_size >= MAX_PATH-12 && sz < MAX_PATH-12) { \
+    in_out_wide_path[0] = L'\\'; in_out_wide_path[1] = L'\\'; \
+    in_out_wide_path[2] = L'?'; in_out_wide_path[3] = L'\\'; \
+    wcscpy(in_out_wide_path+4, tmp); \
+    in_out_size += 4; \
+  } else { \
+    wcscpy(in_out_wide_path, tmp); \
+  } \
+  in_out_wide_path[in_out_size] = 0; \
 }
 
 #endif /* __SQ_WIN32_FILE_H */