drivers/perf: xgene_pmu: Fix IOB SLOW PMU parser error

This patch fixes the below parser error of the IOB SLOW PMU.

        # perf stat -a -e iob-slow0/cycle-count/ sleep 1
        evenf syntax error: 'iob-slow0/cycle-count/'
                                 \___ parser error

It replaces the "-" character by "_" character inside the PMU name.
Signed-off-by: Hoan Tran <hoan.tran@amperecomputing.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

drivers/perf/xgene_pmu.c

@@ -1463,7 +1463,7 @@ static char *xgene_pmu_dev_name(struct device *dev, u32 type, int id)
 	case PMU_TYPE_IOB:
 		return devm_kasprintf(dev, GFP_KERNEL, "iob%d", id);
 	case PMU_TYPE_IOB_SLOW:
-		return devm_kasprintf(dev, GFP_KERNEL, "iob-slow%d", id);
+		return devm_kasprintf(dev, GFP_KERNEL, "iob_slow%d", id);
 	case PMU_TYPE_MCB:
 		return devm_kasprintf(dev, GFP_KERNEL, "mcb%d", id);
 	case PMU_TYPE_MC: