Add Patch 1001897 by Martin. Disabled modem and ipx networking by default as they depend on libraries not everybody may have. Reduces alarmed firewall people and is nicer on unix hosts as port 23 is a bit tricky

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@1904

configure.in

@@ -177,6 +177,16 @@ else
   AC_MSG_RESULT(no)
 fi
 
+AH_TEMPLATE(C_SDL_SOUND,[Define to 1 to enable SDL_sound support])
+AC_CHECK_HEADER(SDL/SDL_sound.h,have_SDL_sound_h=yes,)
+AC_CHECK_LIB(SDL_sound, Sound_Init, have_SDL_sound_lib=yes,,)
+if test x$have_SDL_sound_h = xyes -a x$have_SDL_sound_lib = xyes ; then
+  LIBS="$LIBS -lSDL_sound"
+  AC_DEFINE(C_SDL_SOUND,1)
+else
+  AC_MSG_WARN([Can't find libSDL_sound, libSDL_sound support disabled])
+fi
+
 dnl Some host detection and actions for them
 case "$target" in
     *-*-cygwin* | *-*-mingw32*)