RFR 8173715: Remove Flat Profiler

[Gerard Ziemski]

hi all,

The FlatProfiler (i.e. -Xprof) has been deprecated in jdk9, and now it’s the time to remove the code and obsolete the -Xprof flag.

issue:           https://bugs.openjdk.java.net/browse/JDK-8173715
jdk repo webrev: http://cr.openjdk.java.net/~gziemski/8173715_rev2_repo/
hotspot webrev:  http://cr.openjdk.java.net/~gziemski/8173715_rev2_hotspot/

Specific files to review:

http://cr.openjdk.java.net/~gziemski/8173715_rev2_repo/common/autoconf/hotspot.m4.udiff.html
http://cr.openjdk.java.net/~gziemski/8173715_rev2_hotspot/make/lib/JvmFeatures.gmk.udiff.html