Older API clients did not use a pointer for `PidsLimit`, so
API requests would always send `0`, resulting in any previous
value to be reset after an update:
Before this patch:
(using a 17.06 Docker CLI):
```bash
docker run -dit --name test --pids-limit=16 busybox
docker container inspect --format '{{json .HostConfig.PidsLimit}}' test
16
docker container update --memory=100M --memory-swap=200M test
docker container inspect --format '{{json .HostConfig.PidsLimit}}' test
0
docker container exec test cat /sys/fs/cgroup/pids/pids.max
max
```
With this patch applied:
(using a 17.06 Docker CLI):
```bash
docker run -dit --name test --pids-limit=16 busybox
docker container inspect --format '{{json .HostConfig.PidsLimit}}' test
16
docker container update --memory=100M --memory-swap=200M test
docker container inspect --format '{{json .HostConfig.PidsLimit}}' test
16
docker container exec test cat /sys/fs/cgroup/pids/pids.max
16
```
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
5861a0db22