fix(Makefile): Remove duplicate operator-sdk goal, simplify code

[olivergondza]

What type of PR is this?

/kind cleanup

What does this PR do / why we need it:

The goal was duplicate with similar (but not same) logic - eliminated.

The implementation was silently picking operator-sdk when on PATH - must be provided through OPERATOR_SDK now. Element of least astonishment.

Conditional Makefile logic removed leveraging native make features.

Have you updated the necessary documentation?

• [n/a] Documentation update is required by this PR.
• [n/a] Documentation has been updated.

Which issue(s) this PR fixes:

None

Test acceptance criteria:

• [n/a] Unit Test
• [n/a] E2E Test

How to test changes / Special notes to the reviewer:

• make bundle
• rm -rf ./bin && make bundle
• make OPERATOR_SDK=/bin/operator-sdk bundle # When installed locally

[openshift-ci]

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[openshift-ci]

Hi @olivergondza. Thanks for your PR.

I'm waiting for a redhat-developer member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[olivergondza]

This goal deps are satisfied when user provided existing installation through OPERATOR_SDK, or when they did not but the file exists. When neither is the case bin/operator-sdk goal kicks in.

[jgwest]

/ok-to-test

[olivergondza]

/retest