Disable verbose mode for DNG SDK on mac/ios.
Disable verbose mode for DNG SDK on mac/ios.

The issue was, that the qDNGReportErrors was not disabled in xcode_settings.

With that also removed the complexety of the dng_sdk.gyp and unified the flags handling.

BUG=26821211
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1641553004

Review URL: https://codereview.chromium.org/1641553004

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