qlge: remove duplicated assignment to mbcp

The assignment to mbcp is identical to the initiatialized value assigned
to mbcp at declaration time a few lines earlier, hence we can remove the
second redundant assignment.  Cleans up clang warning:

drivers/net/ethernet/qlogic/qlge/qlge_mpi.c:209:22: warning:
Value stored to 'mbcp' during its initialization is never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>