emulators/dgen-sdl: Unbreak build with clang 6.

OK sthen@, thanks.

emulators/dgen-sdl/patches/patch-main_cpp

@@ -0,0 +1,25 @@
+$OpenBSD: patch-main_cpp,v 1.3 2018/04/13 14:52:07 edd Exp $
+
+C++11 fixes.
+
+Index: main.cpp
+--- main.cpp.orig
++++ main.cpp
+@@ -82,7 +82,7 @@ static char temp[65536] = "";
+ static void help()
+ {
+   printf(
+-  "DGen/SDL v"VER"\n"
++  "DGen/SDL v" VER "\n"
+   "Usage: dgen [options] [romname [...]]\n\n"
+   "Where options are:\n"
+   "    -v              Print version number and exit.\n"
+@@ -256,7 +256,7 @@ int main(int argc, char *argv[])
+ 	{
+ 	case 'v':
+ 	  // Show version and exit
+-	  printf("DGen/SDL version "VER"\n");
++	  printf("DGen/SDL version " VER "\n");
+ 	  return 0;
+ 	case 'r':
+ 	  // Parse another RC file or stdin