RFR: 8280840: Update libFFI to 3.4.2 [v2]

[Alexander Matveev]

> LibFFI updated to 3.4.2. No additional changes to our code, libffi code or build system were required. Tested on all platforms.

Alexander Matveev has updated the pull request incrementally with one additional commit since the last revision:

  8280840: Update libFFI to 3.4.2 [v3]

-------------

Changes:
  - all: https://git.openjdk.java.net/jfx/pull/738/files
  - new: https://git.openjdk.java.net/jfx/pull/738/files/2ca3a52a..a06a3e65

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jfx&pr=738&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jfx&pr=738&range=00-01

  Stats: 9 lines in 1 file changed: 0 ins; 0 del; 9 mod
  Patch: https://git.openjdk.java.net/jfx/pull/738.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/738/head:pull/738

PR: https://git.openjdk.java.net/jfx/pull/738