KVM: x86: Use non-atomic bit ops to manipulate "shadow" MSR intercepts

KVM: x86: Use non-atomic bit ops to manipulate "shadow" MSR intercepts

Manipulate the MSR bitmaps using non-atomic bit ops APIs (two underscores),
as the bitmaps are per-vCPU and are only ever accessed while vcpu->mutex is
held.

Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Link: https://lore.kernel.org/r/20250610225737.156318-8-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>