perf list: Fix s390 counter long description for L1D_RO_EXCL_WRITES

Command

  # perf list --long-desc pmu

lists the long description of the available counters. For counter
named L1D_RO_EXCL_WRITES on machine types 3906 and 3907 the long
description contains the counter number 'Counter:128 Name:'
prefix. This is wrong.

The fix changes the description text and removes this prefix.

Output before:

  [root@m35lp76 perf]# ./perf list --long-desc pmu
   ...
   L1D_ONDRAWER_L4_SOURCED_WRITES
    [A directory write to the Level-1 Data cache directory where the
     returned cache line was sourced from On-Drawer Level-4 cache]

   L1D_RO_EXCL_WRITES
    [Counter:128 Name:L1D_RO_EXCL_WRITES A directory write to the Level-1
     Data cache where the line was originally in a Read-Only state in the
     cache but has been updated to be in the Exclusive state that allows
     stores to the cache line]

   ...

Output after:

  [root@m35lp76 perf]# ./perf list --long-desc pmu
   ...
   L1D_ONDRAWER_L4_SOURCED_WRITES
    [A directory write to the Level-1 Data cache directory where the
     returned cache line was sourced from On-Drawer Level-4 cache]

   L1D_RO_EXCL_WRITES
    [L1D_RO_EXCL_WRITES A directory write to the Level-1
     Data cache where the line was originally in a Read-Only state in the
     cache but has been updated to be in the Exclusive state that allows
     stores to the cache line]

   ...

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fixes: 109d59b900 ("perf vendor events s390: Add JSON files for IBM z14")
Link: http://lkml.kernel.org/r/20190329133337.60255-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/pmu-events/arch/s390/cf_z14/extended.json

@@ -4,7 +4,7 @@
 		"EventCode": "128",
 		"EventName": "L1D_RO_EXCL_WRITES",
 		"BriefDescription": "L1D Read-only Exclusive Writes",
-		"PublicDescription": "Counter:128	Name:L1D_RO_EXCL_WRITES A directory write to the Level-1 Data cache where the line was originally in a Read-Only state in the cache but has been updated to be in the Exclusive state that allows stores to the cache line"
+		"PublicDescription": "L1D_RO_EXCL_WRITES A directory write to the Level-1 Data cache where the line was originally in a Read-Only state in the cache but has been updated to be in the Exclusive state that allows stores to the cache line"
 	},
 	{
 		"Unit": "CPU-M-CF",