scsi: megaraid_sas: Fix the search of first memory bar

scsi: megaraid_sas: Fix the search of first memory bar

Orabug: 25568930

The 2nd parameter of 'find_first_bit' is the number of bits to search.
In this case, we are passing 'sizeof(unsigned long)' which is likely to
be 4.

It is likely that the number of bits in a long was expected here, so use
BITS_PER_LONG instead.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
(cherry picked from commit 51f9039ffd751dee54fe26609df645bfd128b1d0)
Signed-off-by: Brian Maly <brian.maly@oracle.com>
Conflicts:
	drivers/scsi/megaraid/megaraid_sas_base.c