x86/pmu: Drop wrappers that just passthrough pmu_caps fields

Drop wrappers that are and always will be pure passthroughs of pmu_caps
fields, e.g. the number of fixed/general_purpose counters can always be
determined during PMU initialization and doesn't need runtime logic.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221102225110.3023543-18-seanjc@google.com