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/credentials.rst

@@ -291,7 +291,7 @@ for example), it must be considered immutable, barring two exceptions:
 
  1. The reference count may be altered.
 
- 2. Whilst the keyring subscriptions of a set of credentials may not be
+ 2. While the keyring subscriptions of a set of credentials may not be
     changed, the keyrings subscribed to may have their contents altered.
 
 To catch accidental credential alteration at compile time, struct task_struct
@@ -358,7 +358,7 @@ Once a reference has been obtained, it must be released with ``put_cred()``,
 Accessing Another Task's Credentials
 ------------------------------------
 
-Whilst a task may access its own credentials without the need for locking, the
+While a task may access its own credentials without the need for locking, the
 same is not true of a task wanting to access another task's credentials.  It
 must use the RCU read lock and ``rcu_dereference()``.
 
@@ -382,7 +382,7 @@ This should be used inside the RCU read lock, as in the following example::
 	}
 
 Should it be necessary to hold another task's credentials for a long period of
-time, and possibly to sleep whilst doing so, then the caller should get a
+time, and possibly to sleep while doing so, then the caller should get a
 reference on them using::
 
 	const struct cred *get_task_cred(struct task_struct *task);
@@ -442,7 +442,7 @@ duplicate of the current process's credentials, returning with the mutex still
 held if successful.  It returns NULL if not successful (out of memory).
 
 The mutex prevents ``ptrace()`` from altering the ptrace state of a process
-whilst security checks on credentials construction and changing is taking place
+while security checks on credentials construction and changing is taking place
 as the ptrace state may alter the outcome, particularly in the case of
 ``execve()``.