Simplify OSS test by removing OpenBSD specific location of the soundcard.h header

OpenBSD has long since stopped using OSS. Remove checking for OpenBSD specific header.

configure

@@ -21007,10 +21007,6 @@ fi
     #  it on if you really want, though.
     if test x$enable_oss = xmaybe; then
         enable_oss=yes
-        case "$host" in
-            *-*-openbsd*)
-                enable_oss=no;;
-        esac
     fi
 
     if test x$enable_audio = xyes -a x$enable_oss = xyes; then
@@ -21036,33 +21032,6 @@ _ACEOF
 if ac_fn_c_try_compile "$LINENO"
 then :
   have_oss=yes
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
-        fi
-        if test x$have_oss != xyes; then
-            cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-
-              #include <soundcard.h>
-
-int
-main (void)
-{
-
-              int arg = SNDCTL_DSP_SETFRAGMENT;
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"
-then :
-
-            have_oss=yes
-
-printf "%s\n" "#define SDL_AUDIO_DRIVER_OSS_SOUNDCARD_H 1" >>confdefs.h
-
-
 fi
 rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
         fi
@@ -21078,7 +21047,7 @@ printf "%s\n" "#define SDL_AUDIO_DRIVER_OSS 1" >>confdefs.h
 
             # We may need to link with ossaudio emulation library
             case "$host" in
-                *-*-openbsd*|*-*-netbsd*)
+                *-*-netbsd*)
                     EXTRA_LDFLAGS="$EXTRA_LDFLAGS -lossaudio";;
             esac
         fi
@@ -32564,4 +32533,3 @@ if test -n "$ac_unrecognized_opts" && test "$enable_option_checking" != no; then
 printf "%s\n" "$as_me: WARNING: unrecognized options: $ac_unrecognized_opts" >&2;}
 fi
 
-