[PATCH 18/20] Documentation: security/keys: eliminate duplicated word

[Mimi Zohar]

On Tue, 2020-07-07 at 11:04 -0700, Randy Dunlap wrote:
> Drop the doubled word "in".
> 
> Signed-off-by: Randy Dunlap <rdunlap at infradead.org>

Reviewed-by: Mimi Zohar <zohar at linux.ibm.com>