perf/x86/intel: Add a distinct name for Granite Rapids

Currently, the Sapphire Rapids and Granite Rapids share the same PMU
name, sapphire_rapids. Because from the kernel’s perspective, GNR is
similar to SPR. The only key difference is that they support different
extra MSRs. The code path and the PMU name are shared.

However, from end users' perspective, they are quite different. Besides
the extra MSRs, GNR has a newer PEBS format, supports Retire Latency,
supports new CPUID enumeration architecture, doesn't required the
load-latency AUX event, has additional TMA Level 1 Architectural Events,
etc. The differences can be enumerated by CPUID or the PERF_CAPABILITIES
MSR. They weren't reflected in the model-specific kernel setup.
But it is worth to have a distinct PMU name for GNR.

Fixes: a6742cb9 ("perf/x86/intel: Fix the FRONTEND encoding on GNR and MTL")
Suggested-by: Ahmad Yasin <ahmad.yasin@intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20240708193336.1192217-3-kan.liang@linux.intel.com