scsi: mvsas: Fix typos in per-phy comments and SAS cmd port registers

Spelling fixes:
Deocder --> Decoder
Memroy --> Memory

This is a non-functional change aimed at improving code clarity.

Signed-off-by: Ankit Chauhan <ankitchauhan2065@gmail.com>
Link: https://lore.kernel.org/r/20250528110604.59528-1-ankitchauhan2065@gmail.com


Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>