Documentation: Use "while" instead of "whilst"

Whilst making an unrelated change to some Documentation, Linus sayeth:

  | Afaik, even in Britain, "whilst" is unusual and considered more
  | formal, and "while" is the common word.
  |
  | [...]
  |
  | Can we just admit that we work with computers, and we don't need to
  | use þe eald Englisc spelling of words that most of the world never
  | uses?

dictionary.com refers to the word as "Chiefly British", which is
probably an undesirable attribute for technical documentation.

Replace all occurrences under Documentation/ with "while".

Cc: David Howells <dhowells@redhat.com>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/security/keys/request-key.rst

@@ -132,7 +132,7 @@ Negative Instantiation And Rejection
 Rather than instantiating a key, it is possible for the possessor of an
 authorisation key to negatively instantiate a key that's under construction.
 This is a short duration placeholder that causes any attempt at re-requesting
-the key whilst it exists to fail with error ENOKEY if negated or the specified
+the key while it exists to fail with error ENOKEY if negated or the specified
 error if rejected.
 
 This is provided to prevent excessive repeated spawning of /sbin/request-key