tools: disable building qemu-trad per default

Using qemu-traditional as device model is deprecated for some time now.

So change the default for building it to "disable". This will affect
ioemu-stubdom, too, as there is a direct dependency between the two.

Today it is possible to use a PVH/HVM Linux-based stubdom as device
model. Additionally using ioemu-stubdom isn't really helping for
security, as it requires to run a very old and potentially buggy qemu
version in a PV domain. This is adding probably more security problems
than it is removing by using a stubdom.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Acked-by: Ian Jackson <iwj@xenproject.org>
Release-acked-by: Ian Jackson <iwj@xenproject.org>

stubdom/configure

@@ -2286,14 +2286,6 @@ fi
 # Check whether --enable-qemu-traditional was given.
 if test "${enable_qemu_traditional+set}" = set; then :
   enableval=$enable_qemu_traditional;
-else
-
-    case "$host_cpu" in
-        i[3456]86|x86_64)
-           enable_qemu_traditional="yes";;
-        *) enable_qemu_traditional="no";;
-    esac
-
 fi
 
 if test "x$enable_qemu_traditional" = "xyes"; then :

stubdom/configure.ac

@@ -27,13 +27,7 @@ AX_STUBDOM_DEFAULT_ENABLE([xenstorepvh-stubdom], [xenstorepvh])
 AX_STUBDOM_CONDITIONAL([vtpm-stubdom], [vtpm])
 AX_STUBDOM_CONDITIONAL([vtpmmgr-stubdom], [vtpmmgr])
 
-AC_ARG_ENABLE([qemu-traditional],,,[
-    case "$host_cpu" in
-        i[[3456]]86|x86_64)
-           enable_qemu_traditional="yes";;
-        *) enable_qemu_traditional="no";;
-    esac
-])
+AC_ARG_ENABLE([qemu-traditional])
 AS_IF([test "x$enable_qemu_traditional" = "xyes"], [
     qemu_traditional=y],[
     qemu_traditional=n