Revert "x86: kvm: introduce periodic global clock updates"

Revert "x86: kvm: introduce periodic global clock updates"

This reverts commit 332967a3eac06f6379283cf155c84fe7cd0537c2.

Commit 332967a3eac0 ("x86: kvm: introduce periodic global clock
updates") introduced a 300s interval work to sync ntp corrections
across all vcpus.

Since commit 53fafdbb8b21 ("KVM: x86: switch KVMCLOCK base to
monotonic raw clock"), kvmclock switched to mono raw clock,
we can no longer take ntp into consideration.

Signed-off-by: Lei Chen <lei.chen@smartx.com>
Link: https://patch.msgid.link/20250819152027.1687487-2-lei.chen@smartx.com
Signed-off-by: Sean Christopherson <seanjc@google.com>