RFR: 6699: Remove the photon platform

[Marcus Hirt]

Exactly what it sounds like. :)

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Commit messages:
 - 6699: Remove the photon platform

Changes: https://git.openjdk.java.net/jmc/pull/88/files
 Webrev: https://webrevs.openjdk.java.net/jmc/88/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JMC-6699
  Stats: 149 lines in 5 files changed: 0 ins; 149 del; 0 mod
  Patch: https://git.openjdk.java.net/jmc/pull/88.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/88/head:pull/88

PR: https://git.openjdk.java.net/jmc/pull/88