KVM: VMX: remove unneeded vmx_load_host_state() calls.

vmx_load_host_state() does not handle msrs switching (except
MSR_KERNEL_GS_BASE) since commit 26bb0981. Remove call to it
where it is no longer make sense.

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