perf/x86/lbr: Simplify the exposure check for the LBR_INFO registers

The x86_pmu.lbr_info is 0 unless explicitly initialized, so there's
no point checking x86_pmu.intel_cap.lbr_format.

Signed-off-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Link: https://lkml.kernel.org/r/20221125040604.5051-2-weijiang.yang@intel.com