[PATCHES] more d_splice_alias() in ->lookup() instances

[Al Viro]

From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

In the spirit of "thou shalt not push into your tree without
at least posting for review"...

* hostfs conversion of ->lookup() to use of d_splice_alias()
* afs conversions of ->lookup() to use of d_splice_alias()
* hpfs conversion of ->lookup() to use of d_splice_alias(),
leak fix on failure exit.

Stuff is in vfs.git#work.lookup, to go into #for-next if nobody
yells.