KVM: x86: fix vcpu initialization with userspace lapic

Moving the code around broke this rare configuration.
Use this opportunity to finally call lapic reset from vcpu reset.

Reported-by:  <syzbot+fb7a33a4b6c35007a72b@syzkaller.appspotmail.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes: 0b2e9904 ("KVM: x86: move LAPIC initialization after VMCS creation")
Cc: stable@vger.kernel.org
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>