[Base] Remove kMaxPath from Windows, it should not be used

All instances of kMaxPath or MAX_PATH being used have been removed,
and removing this constant is supposed to encourage writing code
without artificial constraints on path length.

src/xenia/base/platform.h

@@ -95,7 +95,6 @@ namespace xe {
 #if XE_PLATFORM_WIN32
 const char kPathSeparator = '\\';
 const wchar_t kWPathSeparator = L'\\';
-const size_t kMaxPath = 260;  // _MAX_PATH
 #else
 const char kPathSeparator = '/';
 const wchar_t kWPathSeparator = L'/';