[lworld] RFR: 8373896: [lworld] Remove now-dead preview patching code

[David Beaumont]

Removing code guarded by now obsolete preview patching property.
This should be a no-op functionally.
Some minor tidying around arguments.cpp since now there's no reason to init the jimage file in the module patching code.

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Commit messages:
 - Removing the obviously dead code

Changes: https://git.openjdk.org/valhalla/pull/1819/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=1819&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8373896
  Stats: 124 lines in 9 files changed: 2 ins; 112 del; 10 mod
  Patch: https://git.openjdk.org/valhalla/pull/1819.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1819/head:pull/1819

PR: https://git.openjdk.org/valhalla/pull/1819