[jdk17u-dev] RFR: 8306408: Fix the format of several tables in building.md

[Zdenek Zambersky]

Backport fixing several tables in `doc/building.md`, so they would display correctly in GitHub. Change set applied almost cleanly to `doc/building.md` (only last table has one more target in original changeset). File `doc/building.html` was regenerated.

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Commit messages:
 - Backport 26755a968665545a151adce79a5227c79724bb6b

Changes: https://git.openjdk.org/jdk17u-dev/pull/2205/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2205&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8306408
  Stats: 101 lines in 2 files changed: 0 ins; 0 del; 101 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2205.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2205/head:pull/2205

PR: https://git.openjdk.org/jdk17u-dev/pull/2205