scsi: message: fusion: Remove unused variable retval

scsi: message: fusion: Remove unused variable retval

The following warning showed up when compiling with W=1.

drivers/message/fusion/mptctl.c: In function ‘mptctl_hp_hostinfo’:
drivers/message/fusion/mptctl.c:2337:8: warning: variable ‘retval’ set but not used [-Wunused-but-set-variable]
  int   retval;

Fixing by removing the variable.

Link: https://lore.kernel.org/r/20220317030325.30526-1-alexander.vorwerk@stud.uni-goettingen.de
Signed-off-by: Alexander Vorwerk <alexander.vorwerk@stud.uni-goettingen.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>