scsi: mpt3sas: Fix event callback log_code value handling

In mpt3sas_scsih_event_callback(), fix a sparse warning when testing the
event log code value by replacing the use of a pointer to the address
storing the event log code with a log code local variable. Doing so,
le32_to_cpu() is used when the log code value is assigned, avoiding a
sparse warning.

Link: https://lore.kernel.org/r/20220307234854.148145-5-damien.lemoal@opensource.wdc.com


Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>