net: dsa: bcm_sf2: Fix 64-bits register writes

The macro to write 64-bits quantities to the 32-bits register swapped
the value and offsets arguments, we want to preserve the ordering of the
arguments with respect to how writel() is implemented for instance:
value first, offset/base second.

Fixes: 246d7f77 ("net: dsa: add Broadcom SF2 switch driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>