KVM: x86/pmu: Rename pmc_is_enabled() to pmc_is_globally_enabled()

The name of function pmc_is_enabled() is a bit misleading. A PMC can
be disabled either by PERF_CLOBAL_CTRL or by its corresponding EVTSEL.
Append global semantics to its name.

Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Like Xu <likexu@tencent.com>
Link: https://lore.kernel.org/r/20230214050757.9623-2-likexu@tencent.com


Signed-off-by: Sean Christopherson <seanjc@google.com>