[foreign-abi] RFR: 8248458: CSupport.toJavaStringInternal should be moved SharedUtils

[Athijegannathan Sundararajan]

toJavaStringInternal method moved to SharedUtils.

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Commit messages:
 - 8248458: CSupport.toJavaStringInternal should be moved SharedUtils

Changes: https://git.openjdk.java.net/panama-foreign/pull/217/files
 Webrev: https://webrevs.openjdk.java.net/panama-foreign/217/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8248458
  Stats: 52 lines in 2 files changed: 25 ins; 22 del; 5 mod
  Patch: https://git.openjdk.java.net/panama-foreign/pull/217.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-foreign pull/217/head:pull/217

PR: https://git.openjdk.java.net/panama-foreign/pull/217