RFR: 8364346: Typo in IR framework README

[Lei Zhu]

Fix typo errors.

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Commit messages:
 - 8364346: Typo in IR framework README

Changes: https://git.openjdk.org/jdk/pull/27688/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=27688&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8364346
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/27688.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27688/head:pull/27688

PR: https://git.openjdk.org/jdk/pull/27688