RFR: 8259864: Cleanup unused Prism files [v2]

[Johan Vos]

> Fix for JDK-8259864
> Remove java and native files that are not used/maintained in prism configurations.

Johan Vos has updated the pull request incrementally with one additional commit since the last revision:

  Process review comments.
  Remove more references to egl{fb/x11}

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Changes:
  - all: https://git.openjdk.java.net/jfx/pull/378/files
  - new: https://git.openjdk.java.net/jfx/pull/378/files/f795f19e..49cee7a9

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jfx&pr=378&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jfx&pr=378&range=00-01

  Stats: 52 lines in 5 files changed: 0 ins; 50 del; 2 mod
  Patch: https://git.openjdk.java.net/jfx/pull/378.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/378/head:pull/378

PR: https://git.openjdk.java.net/jfx/pull/378