scsi: ufs: docs: UFS documentation corrections

Make a variety of corrections to ufs.rst:

 - add spaces around parenthetical phrases
 - correct singular/plural grammar and nouns
 - correct punctuation
 - add article adjectives
 - add hyphens to multi-word adjectives
 - spell Lun as LUN
 - spell upiu as UPIU (in text, not code examples)
 - don't capitalize generic "specification"

Link: https://lore.kernel.org/r/20220307013224.5130-1-rdunlap@infradead.org


Cc: Alim Akhtar <alim.akhtar@samsung.com>
Cc: Avri Altman <avri.altman@wdc.com>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>