On Solaris, we used to always add /usr/sbin to the global PATH early in
configure since some tools we need are found there. In JDK-8165161 that
was removed. This had the consequence that configure no longer found
dtrace unless the user had /usr/sbin in the PATH. When configure doesn't
find dtrace, it will by default simply disable dtrace support in the
hotspot build. This patch fixes two things.
* Since Oracle builds on Solaris expect dtrace to be enabled, I added
--enable-dtrace to the Jib configuration for Solaris profiles. That way
we get an early failure if dtrace is missing.
* I added /usr/sbin to the path specifically when searching for dtrace
since that is a known location for the tool that is not always present
in the user path.