RFR: 8368565: Adjust comment regarding dependency of libjvm.so to librt [v2]

[Matthias Baesken]

> We have a legacy dependency of libjvm to librt for the` clock_*` functions :
> https://github.com/openjdk/jdk/blob/f993f90c86f89eb0c7f42ebecb45a68eae0bd9ea/make/autoconf/libraries.m4#L139
> 
> But this is for very old systems with distros like RHEL 6 or SLES11 with glibc 2.16 or older, where the clock_ functions were still in librt ; but those ancient distros play no role any more for current JDK26.
> On the other hand, we now use the `timer_*` functions from librt e.g. in JFR and these are _really_  in librt so the comment should be adjusted.

Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:

  adjust/simplify comment regarding librt

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/27473/files
  - new: https://git.openjdk.org/jdk/pull/27473/files/980de745..745bf7f4

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=27473&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=27473&range=00-01

  Stats: 4 lines in 1 file changed: 0 ins; 3 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/27473.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27473/head:pull/27473

PR: https://git.openjdk.org/jdk/pull/27473