Older versions of Mac OS X do not support cp -a. The cp man page indicates
that -a is equivalent to -pPR.

Signed-off-by: Evan Miller <emmiller@gmail.com>
Message-Id: <40635C6E-059A-4146-B1E2-F6376700EE85@gmail.com>
[Leave out -R, these are files and not directories. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>