RFR: 8276540: Howl Full CardSet container iteration marks too many cards

[Thomas Schatzl]

Hi all,

  can I have reviews for this change that fixes how many cards are being iterated over during Howl Full CardSet container iteration? There is no need to iterate over `max_cards_in_region()` cards, it is sufficient to iterate just over the area that this Howl partition represents, i.e. `num_cards_in_howl_bitmap()`.

I will change the way to iterate over this card set container in JDK-8276548 to keep this change small.

Testing: tier1-5 (with JDK-8276548).

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

Commit messages:
 - Fix

Changes: https://git.openjdk.java.net/jdk/pull/6229/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=6229&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8276540
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6229.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6229/head:pull/6229

PR: https://git.openjdk.java.net/jdk/pull/6229