scsi: lpfc: Provide description for lpfc_mem_alloc()'s 'align' param

Fixes the following W=1 kernel build warning(s):

drivers/scsi/lpfc/lpfc_mem.c:85: warning: Function parameter or member 'align' not described in 'lpfc_mem_alloc'

Link: https://lore.kernel.org/r/[e-mail]
Cc: James Smart <[e-mail]>
Cc: Dick Kennedy <[e-mail]>
Cc: Sumit Semwal <[e-mail]>
Cc: "Christian König" <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Signed-off-by: Lee Jones <[e-mail]>
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/scsi/lpfc/lpfc_mem.c

···
 /**
  * lpfc_mem_alloc - create and allocate all PCI and memory pools
  * @phba: HBA to allocate pools for
+ * @align: alignment requirement for blocks; must be a power of two
  *
  * Description: Creates and allocates PCI pools lpfc_mbuf_pool,
  * lpfc_hrb_pool.  Creates and allocates kmalloc-backed mempools