msm: ipa3: fix odu debugfs

Fix a bug in IPA ODU where debugfs directory was deleted after
creation.

CRs-Fixed: 1015545
Change-Id: I5aad7032f3f8048216a41765f1cf91fde98f6ade
Acked-by: Ady Abraham <adya@qti.qualcomm.com>
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>