target-ppc: POWER7+ supports the MSR_VSX bit Without MSR_VSX we die early during a Linux boot. Signed-off-by: Anton Blanchard <anton@samba.org> Reviewed-by: Cédric Le Goater <clg@fr.ibm.com> Tested-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Andreas Färber <afaerber@suse.de>