LU-17583 llite: getattr/open should not revalidate dentry

LU-17583 llite: getattr/open should not revalidate dentry

ll_getattr() and ll_intent_file_open() do not perform a lookup, it
get the attr and ldlm locks by FID (inode). So this should not
revalidate the dentry, otherwise it may produce dir cache
inconsistencies (e.g: with cwd fd).

Add a regression test: sanityn 31s, 31t

Fixes: 14ca315 ("LU-10948 llite: Revalidate dentries in ll_intent_file_open")
Fixes: 92fadf9 ("LU-15200 llite: revalidate dentry if LOOKUP lock fetched")
Test-Parameters: testlist=sanityn env=ONLY=31s,ONLY_REPEAT=20
Test-Parameters: testlist=sanityn env=ONLY=31t,ONLY_REPEAT=20
Signed-off-by: Etienne AUJAMES <eaujames@ddn.com>
Change-Id: Ic9823cddf37373dc95f4de3219c88c0fa0600fa7
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/54354
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Alex Zhuravlev <bzzz@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Lai Siyao <lai.siyao@whamcloud.com>