arch-arm: Enable PMSELR_EL0 read in PMU

Change-Id: Ic1ec1d03464a7ce42295cee8a9f4ebcd3e90def1
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17948
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

src/arch/arm/pmu.cc

diff --git a/src/arch/arm/pmu.cc b/src/arch/arm/pmu.cc
index 62353cf..93d4f5e 100644
--- a/src/arch/arm/pmu.cc
+++ b/src/arch/arm/pmu.cc
@@ -333,6 +333,7 @@
       case MISCREG_PMSWINC: // Software Increment Register (RAZ)
         return 0;
 
+      case MISCREG_PMSELR_EL0:
       case MISCREG_PMSELR:
         return reg_pmselr;