CVE-2022-48932 net/mlx5: DR, Fix slab-out-of-bounds in mlx5_cmd_dr_create_fte

In the Linux kernel, the following vulnerability has been resolved:

net/mlx5: DR, Fix slab-out-of-bounds in mlx5_cmd_dr_create_fte

When adding a rule with 32 destinations, we hit the following out-of-band
access issue:

BUG: KASAN: slab-out-of-bounds in mlx5_cmd_dr_create_fte+0x18ee/0x1e70

This patch fixes the issue by both increasing the allocated buffers to
accommodate for the needed actions and by checking the number of actions
to prevent this issue when a rule with too many actions is provided.