IB/iser: Rename struct fast_reg_descriptor -> iser_fr_desc

Avoid struct names without iser_ prefix.

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --cc drivers/infiniband/ulp/iser/iscsi_iser.h
Simple merge

diff --cc drivers/infiniband/ulp/iser/iser_memory.c
Simple merge

diff --cc drivers/infiniband/ulp/iser/iser_verbs.c
Simple merge