Older gcc versions (such as the one in SLES11) get confused when you declare
a typedef on the same struct twice.
To work around that limitation, let's extract the QEMUMachine typedef into a
separate header file that is guarded by preprocessor duplicate include checks.
This fixes the following type of compile errors for me:
In file included from vl.c:125:
include/hw/xen/xen.h:39: error: redefinition of typedef "QEMUMachine"
include/sysemu/kvm.h:155: error: previous declaration of "QEMUMachine" was here
Signed-off-by: Alexander Graf <agraf@suse.de>