RFR: 8371626: [linux] use icf=all for linking libraries

[Matthias Baesken]

Identical code folding can reduce the size of some libs, especially libjvm. However not all linkers support the flag/feature so we have to limit it to some environments.
See for example this manpage :
https://manpages.debian.org/testing/lld-7/ld.lld-7.1


sizes of libjvm.so with / without -icf=all
linux aarch64 : 25888 / 27112 K
linux x86_64 : 27952 / 29072 K


(for most other native libs the identical code folding has no effect, because there is nothing to fold)

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Commit messages:
 - JDK-8371626

Changes: https://git.openjdk.org/jdk/pull/28236/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28236&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8371626
  Stats: 7 lines in 1 file changed: 7 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/28236.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28236/head:pull/28236

PR: https://git.openjdk.org/jdk/pull/28236