KVM: x86: update KVM_SAVE_MSRS_BEGIN to correct value

When MSR_KVM_PV_EOI_EN was added to msrs_to_save array
KVM_SAVE_MSRS_BEGIN was not updated accordingly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>