[core distrib].c: Create log before opening SSA devices

as was done for acm.c in commit fcde00d7229938386042f68b6664c00b5dc18034
acm.c: Create ibacm.log before opening SSA devices

Signed-off-by: Hal Rosenstock <hal@mellanox.com>
acm.c: Cosmetic formatting change

Signed-off-by: Hal Rosenstock <hal@mellanox.com>