configure: enable kvm on x32

Here's a trivial change to enable kvm on x32 architecture.
I'm not 100% sure the result works correctly in all cases,
but this is a good start and in theory everything should
work.
Signed-off-by: NAdam Borowski <kilobyte@angband.pl>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>

configure

@@ -5268,7 +5268,9 @@ case "$target_name" in
       \( "$target_name" = "ppcemb" -a "$cpu" = "ppc64" \) -o \
       \( "$target_name" = "mipsel" -a "$cpu" = "mips" \) -o \
       \( "$target_name" = "x86_64" -a "$cpu" = "i386"   \) -o \
-      \( "$target_name" = "i386"   -a "$cpu" = "x86_64" \) \) ; then
+      \( "$target_name" = "i386"   -a "$cpu" = "x86_64" \) -o \
+      \( "$target_name" = "x86_64" -a "$cpu" = "x32"   \) -o \
+      \( "$target_name" = "i386"   -a "$cpu" = "x32" \) \) ; then
       echo "CONFIG_KVM=y" >> $config_target_mak
       if test "$vhost_net" = "yes" ; then
         echo "CONFIG_VHOST_NET=y" >> $config_target_mak