RFR: 8279958: Provide configure hints for Alpine/apk package managers

[Aleksey Shipilev]

Our build system provides helpful hints about the packages to install to resolve the build-time dependencies. It can be amended to include Alpine/apk package managers. Noticed this when trying to build mainline OpenJDK on Alpine 3. 

Additional testing:
 - [x] Was able to build on clean Alpine 3 with these hints

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Commit messages:
 - Fix

Changes: https://git.openjdk.java.net/jdk/pull/7064/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7064&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8279958
  Stats: 25 lines in 1 file changed: 23 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7064.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7064/head:pull/7064

PR: https://git.openjdk.java.net/jdk/pull/7064