octeontx2-pf: Fix sizeof() mismatch

An incorrect sizeof() is being used, sizeof(u64 *) is not correct,
it should be sizeof(*sq->sqb_ptrs).

Addresses-Coverity: ("Sizeof not portable (SIZEOF_MISMATCH)")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20201102134601.698436-1-colin.king@canonical.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>