s390 introduced the Processor Activity Instrumentation (PAI) counter
facility on LPAR and virtual machines z/VM for models 3931 and 3932.

These counters are stored as raw data in the perf.data file and are
displayed with:

 # perf report -i /tmp//perfout-635468 -D | grep Counter
	Counter:007 <unknown> Value:0x00000000000186a0
	Counter:032 <unknown> Value:0x0000000000000001
	Counter:032 <unknown> Value:0x0000000000000001
	Counter:032 <unknown> Value:0x0000000000000001
 #

However on z/VM virtual machines, the counter names are not retrieved
from the PMU and are shown as '<unknown>'.  This is caused by the CPU
string saved in the mapfile.csv for this machine:

   ^IBM.393[12].*3\.7.[[:xdigit:]]+$,3,cf_z16,core

This string contains the CPU Measurement facility first and second
version number and authorization level (3\.7.[[:xdigit:]]+).  These
numbers do not apply to the PAI counter facility.  In fact they can be
omitted.

Shorten the CPU identification string for this machine to manufacturer
and model. This is sufficient for all PMU devices.

Output after:

 # perf report -i /tmp//perfout-635468 -D | grep Counter
	Counter:007 km_aes_128 Value:0x00000000000186a0
	Counter:032 kma_gcm_aes_256 Value:0x0000000000000001
	Counter:032 kma_gcm_aes_256 Value:0x0000000000000001
	Counter:032 kma_gcm_aes_256 Value:0x0000000000000001
 #

Fixes: b539deaf ("perf report: Add s390 raw data interpretation for PAI counters")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: https://lore.kernel.org/r/20240404064806.1362876-1-tmricht@linux.ibm.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>