mds: for logging generate only 10 final components of dentry path

mds: for logging generate only 10 final components of dentry path

Generating full absolute path for dentries for printing in MDS logs
slows the down the FS to a great extent especially when the path is very
long (imagine a path with 2000 components). Printing such long paths in
MDS logs is not only pointless but also greatly reduces the readability
of MDS logs.

Therefore, generate only 10 final components of the dentry paths for logging.

Fixes: https://tracker.ceph.com/issues/72779
Signed-off-by: Rishabh Dave <ridave@redhat.com>