[jdk17u-dev] RFR: 8301074: Replace NULL with nullptr in share/opto/

[Goetz Lindenmaier]

A lot of hunks were rejected. I replaced all remaining NULL with sed help.

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Commit messages:
 - Fix failed hunks and other NULLS by sed
 - Backport 5726d31e56530bbe7dee61ae04b126e20cb3611d

Changes: https://git.openjdk.org/jdk17u-dev/pull/1293/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1293&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8301074
  Stats: 5347 lines in 110 files changed: 1 ins; 0 del; 5346 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1293.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1293/head:pull/1293

PR: https://git.openjdk.org/jdk17u-dev/pull/1293