scsi: mpt3sas: Fix incorrectly assigned error return and check

Currently the call to _base_static_config_pages() is assigning the error
return to variable 'rc' but checking the error return in error 'r'. Fix
this by assigning the error return to variable 'r' instead of 'rc'.

Link: https://lore.kernel.org/r/20210804134940.114011-1-colin.king@canonical.com
Fixes: 19a622c3

 ("scsi: mpt3sas: Handle firmware faults during first half of IOC init")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Addresses-Coverity: ("Unused value")