Make the cleanPodPolicyPointer function global

[tenzen-y]

What this PR does / why we need it:
I made the cleanPodPolicyPointer function global.

Which issue(s) this PR fixes (optional, in Fixes #<issue number>, #<issue number>, ... format, will close the issue(s) when PR gets merged):
Fixes #

Checklist:

• Docs included if any changes are user facing

[tenzen-y]

/assign @johnugeorge @terrytangyuan

[coveralls]

Pull Request Test Coverage Report for Build 5517340751

• 6 of 8 (75.0%) changed or added relevant lines in 7 files are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.02%) to 32.939%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/apis/kubeflow.org/v1/paddlepaddle_defautls.go	0	1	0.0%
pkg/apis/kubeflow.org/v1/pytorch_defaults.go	0	1	0.0%

Files with Coverage Reduction	New Missed Lines	%
pkg/controller.v1/mpi/mpijob_controller.go	2	79.17%

Totals
Change from base Build 5511536982:	-0.02%
Covered Lines:	3172
Relevant Lines:	9630

---

💛 - Coveralls

[terrytangyuan]

Thanks!

/lgtm

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: tenzen-y, terrytangyuan

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [terrytangyuan]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment