net/ice: fix max entry number for ACL normal priority

net/ice: fix max entry number for ACL normal priority

For ACL, there are three entry priorities: LOW, NORMAL, HIGH.
Low priority starts from the highest index, 25% of total entries;
Normal priority starts from the highest index, 50% of total entries;
High priority starts from the lowest index, 25% of total entries.

Each TCAM block has 512 entries of 40 bits. Currently, there is a
scenario in which multiple TCAM blocks are cascaded. It means the
total entries are 512. The default priority is NORMAL, so the max
entry is 256, not 512. This patch changes the max entry number for
NORMAL priority.

Fixes: 40d466fa9f76 ("net/ice: support ACL filter in DCF")
Cc: stable@dpdk.org
Signed-off-by: Simei Su <simei.su@intel.com>
Acked-by: Qi Zhang <qi.z.zhang@intel.com>