Remove PAL_printf_arg_remover

[kangaroo]

The current code seems to assume that va_lists need manual advancing.
This is against the standard, and actually breaks many things rather badly on OSX.
Remove it, and favor va_copy as needed. Fixes all PAL tests in debug and release mode on OS X

[dnfclas]

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[sergiy-k]

LGTM.

[dnfclas]

@kangaroo, Thanks for signing the contribution license agreement so quickly! Actual humans will now validate the agreement and then evaluate the PR.

Thanks, DNFBOT;

[sergiy-k]

@janvorli Could you please take a look as well and give second approval so we can merge this change? Thank you.

[kangaroo]

Is this blocked on something? Can someone give second review please?

[jkotas]

LGTM