KVM: x86/pmu: Rename pmc_speculative_in_use() to pmc_is_locally_enabled()

KVM: x86/pmu: Rename pmc_speculative_in_use() to pmc_is_locally_enabled()

Rename pmc_speculative_in_use() to pmc_is_locally_enabled() to better
capture what it actually tracks, and to show its relationship to
pmc_is_globally_enabled().  While neither AMD nor Intel refer to event
selectors or the fixed counter control MSR as "local", it's the obvious
name to pair with "global".

As for "speculative", there's absolutely nothing speculative about the
checks.  E.g. for PMUs without PERF_GLOBAL_CTRL, from the guest's
perspective, the counters are "in use" without any qualifications.

No functional change intended.

Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20250805190526.1453366-13-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>