[SCSI] libfc: avoid exchanges collision during lport reset

[SCSI] libfc: avoid exchanges collision during lport reset

Currently timer delay is large and is using msleep to avoid
avoid exchanges collision across lport reset, so instead
do this by initializing exches pool indexes during
reset also.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Tested-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
(cherry picked from commit b6e3c84034b93e6acc895711f74730e235dfe9d2)

Signed-off-by: Joe Jin <joe.jin@oracle.com>