KVM: X86: Reset the three MSR list number variables to 0 in kvm_init_msr_list()

When applying commit 7a5ee6ed ("KVM: X86: Fix initialization of MSR
lists"), it forgot to reset the three MSR lists number varialbes to 0
while removing the useless conditionals.

Fixes: 7a5ee6ed (KVM: X86: Fix initialization of MSR lists)
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>