RFR: CODETOOLS-7902953: jcstress: Minor touchups for status line and percent reporting

[Aleksey Shipilev]

See the changeset.

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

Commit messages:
 - CODETOOLS-7902953: jcstress: Minor touchups for status line and percent reporting

Changes: https://git.openjdk.java.net/jcstress/pull/61/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jcstress&pr=61&range=00
  Issue: https://bugs.openjdk.java.net/browse/CODETOOLS-7902953
  Stats: 4 lines in 2 files changed: 3 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jcstress/pull/61.diff
  Fetch: git fetch https://git.openjdk.java.net/jcstress pull/61/head:pull/61

PR: https://git.openjdk.java.net/jcstress/pull/61