perf jvmti: Give hints about package names needed to build

Give as examples of package names to install to have this built for
fedora and debian, to help the user a bit.

The part from 'e.g.:' onwards:

  No openjdk development package found, please install JDK package, e.g. openjdk-8-jdk, java-1.8.0-openjdk-devel

Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: William Cohen <wcohen@redhat.com>
Link: https://lkml.kernel.org/n/tip-edbi4r2pvzn7no6ebxbtczng@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Makefile.config

@@ -847,7 +847,7 @@ ifndef NO_JVMTI
   ifeq ($(feature-jvmti), 1)
     $(call detected_var,JDIR)
   else
-    $(warning No openjdk development package found, please install JDK package)
+    $(warning No openjdk development package found, please install JDK package, e.g. openjdk-8-jdk, java-1.8.0-openjdk-devel)
     NO_JVMTI := 1
   endif
 endif