Add a helper to probe KVM's "enable_pmu" param, open coding strings in multiple places is just asking for false negatives and/or runtime errors due to typos. Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Tested-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Link: https://lore.kernel.org/r/20240109230250.424295-23-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>