[foreign-memaccess+abi] RFR: Fix style and remove redundant method

[Per Minborg]

This PR fixes some code style issues and removes a redundant method.

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Commit messages:
 - Fix style and remove redundant method

Changes: https://git.openjdk.org/panama-foreign/pull/733/files
 Webrev: https://webrevs.openjdk.org/?repo=panama-foreign&pr=733&range=00
  Stats: 22 lines in 6 files changed: 1 ins; 9 del; 12 mod
  Patch: https://git.openjdk.org/panama-foreign/pull/733.diff
  Fetch: git fetch https://git.openjdk.org/panama-foreign pull/733/head:pull/733

PR: https://git.openjdk.org/panama-foreign/pull/733