vfs: tidy up fs/namei.c byte-repeat word constants

In commit commit 1de5b41cd3b2 ("fs/namei.c: fix warnings on 32-bit")
Andrew said that there must be a tidier way of doing this.

This is that tidier way.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --cc fs/namei.c
Simple merge