mac-capture: Fix incorrect enum comparison

[jcm93]

Description

macOS Audio Capture was using the incorrect capture type enum member to check the capture method on initialization. Because the default was zero, and because the incorrect enum would typically be zero-initialized anyway, this went unnoticed. The correct member enum is being used everywhere else in macOS Audio Capture.

Motivation and Context

AppleClang in Xcode 16.3 flags this as a non-matching enum type in the comparison, breaking the build. For some reason earlier AppleClang in earlier SDKs did not flag this as a warning.

Fixes #12034.

How Has This Been Tested?

Verified the build now works locally with Xcode 16.3 and that macOS Audio Capture still works as intended.

Types of changes

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• My code has been run through clang-format.
• I have read the contributing document.
• My code is not on the master branch.
• The code has been tested.
• All commit messages are properly formatted and commits squashed where appropriate.
• I have included updates to all appropriate documentation.