util: handle Close() errors in pidlimit
util: handle Close() errors in pidlimit

A new version of gosec insists on handling errors returned by Close():

    [/go/src/github.com/ceph/ceph-csi/internal/util/pidlimit.go:44] - G307 (CWE-): Deferring unsafe method "*os.File" on type "Close" (Confidence: HIGH, Severity: MEDIUM)
      > defer cgroup.Close()

    [/go/src/github.com/ceph/ceph-csi/internal/util/pidlimit.go:78] - G307 (CWE-): Deferring unsafe method "*os.File" on type "Close" (Confidence: HIGH, Severity: MEDIUM)
      > defer f.Close()

    [/go/src/github.com/ceph/ceph-csi/internal/util/pidlimit.go:113] - G307 (CWE-): Deferring unsafe method "*os.File" on type "Close" (Confidence: HIGH, Severity: MEDIUM)
      > defer f.Close()

Signed-off-by: Niels de Vos <7bda0c0ee7f47171cc808e9e60292cbc5d8140dd@redhat.com>

ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi