Documentation: block: eliminate duplicated word

Change the doubled word "the" to "to the".
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Link: https://lore.kernel.org/r/20200707180414.10467-3-rdunlap@infradead.orgSigned-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/block/pr.rst

@@ -9,7 +9,7 @@ access to block devices to specific initiators in a shared storage
 setup.
 
 This document gives a general overview of the support ioctl commands.
-For a more detailed reference please refer the the SCSI Primary
+For a more detailed reference please refer to the SCSI Primary
 Commands standard, specifically the section on Reservations and the
 "PERSISTENT RESERVE IN" and "PERSISTENT RESERVE OUT" commands.