generic/062: filter setfattr --restore symlink-safety warning

attr 2.6.0 (CVE-2026-54371 fix)[0] makes "setfattr --restore" warn when
used without -P and the dump contains a symlink, which generic/062 does.
The warning leaks into the compared output via the setfattr() wrapper
and fails the test. Adding -P isn't portable (older attr doesn't have it),
so filter the warning in the wrapper instead.

[0] https://cgit.git.savannah.nongnu.org/cgit/attr.git/commit/?id=3fb06b9ba314d37035d0877e6de313de754f1ac8

Signed-off-by: Avinesh Kumar <avinesh.kumar@suse.com>
Reviewed-by: Zorro Lang <zlang@kernel.org>
Signed-off-by: Zorro Lang <zlang@kernel.org>