ZTS: Fix pool_state cleanup

[behlendorf]

Motivation and Context

When running the ZTS tests in a different order it was observed that
pool_state.ksh does not wipe one of the vdev labels which can result
in the next test group failing when -f isn't used with zpool create.
In this case, several refreserv test cases failed incorrectly.

Description

The externally faulted vdev should be brought back online and have
its errors cleared before the pool is destroyed. Failure to do so
will leave a vdev with a valid active label. This vdev may then
not be used to create a new pool without the -f flag potentially
leading to subsequent test failures.

Additionally remove an unreachable log_pass from setup.ksh.

How Has This Been Tested?

Without this PR running only the procfs,refreserv test groups:

$ ./scripts/zfs-tests.sh -T procfs,refreserv
Test (Linux): /home/behlendo/src/git/zfs/tests/zfs-tests/tests/functional/procfs/setup (run as root) [00:01] [PASS]
Test (Linux): /home/behlendo/src/git/zfs/tests/zfs-tests/tests/functional/procfs/procfs_list_basic (run as root) [00:10] [PASS]
...
Tests with result of PASS that are unexpected:

Tests with results other than PASS that are unexpected:
    FAIL refreserv/refreserv_multi_raidz (expected PASS)
    FAIL refreserv/refreserv_raidz (expected PASS)

With this PR:

$ ./scripts/zfs-tests.sh -T procfs,refreserv
Test (Linux): /home/behlendo/src/git/zfs/tests/zfs-tests/tests/functional/procfs/setup (run as root) [00:01] [PASS]
Test (Linux): /home/behlendo/src/git/zfs/tests/zfs-tests/tests/functional/procfs/procfs_list_basic (run as root) [00:06] [PASS]
...
Tests with result of PASS that are unexpected:

Tests with results other than PASS that are unexpected:

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Performance enhancement (non-breaking change which improves efficiency)
• Code cleanup (non-breaking change which makes code smaller or more readable)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation (a change to man pages or other documentation)

Checklist:

• My code follows the ZFS on Linux code style requirements.
• I have updated the documentation accordingly.
• I have read the contributing document.
• I have added tests to cover my changes.
• All new and existing tests passed.
• All commit messages are properly formatted and contain Signed-off-by.

[codecov]

Codecov Report

Merging #9777 into master will increase coverage by 13%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #9777      +/-   ##
==========================================
+ Coverage      67%      80%     +13%     
==========================================
  Files         303      385      +82     
  Lines      104240   121475   +17235     
==========================================
+ Hits        69658    96686   +27028     
+ Misses      34582    24789    -9793

Flag	Coverage Δ
#kernel	80% <ø> (?)
#user	67% <ø> (ø)	⬆️

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