perf record: Remove misleading error suggestion

When perf record encounters an error setting up an event it suggests
to enable CONFIG_PERF_EVENTS. This is misleading because:

- Usually it is enabled (it is really hard to disable on x86)

- The problem is usually somewhere else, e.g. the CPU is not supported
or an invalid configuration has been used.

Remove the misleading suggestion.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20180406203812.3087-4-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/evsel.c

@@ -2894,8 +2894,7 @@ int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,
 
 	return scnprintf(msg, size,
 	"The sys_perf_event_open() syscall returned with %d (%s) for event (%s).\n"
-	"/bin/dmesg may provide additional information.\n"
-	"No CONFIG_PERF_EVENTS=y kernel support configured?",
+	"/bin/dmesg | grep -i perf may provide additional information.\n",
 			 err, str_error_r(err, sbuf, sizeof(sbuf)),
 			 perf_evsel__name(evsel));
 }