Merge #13055: qt: Don't log to console by default

Summary:
aee80b0ef9 qt: Don't log to console by default (Wladimir J. van der Laan)

Pull request description:

Default `-printtoconsole` to false for the GUI. GUI programs should not print to the console unnecessarily. For example, when launched by the window manager, the output might end up in the X session log file,
resulting in duplicate logging. On Windows, it is pointless as well because bitcoin-qt isn't a console application.

This same mechanism is used to set `-server` to true by default for bitcoind: https://github.com/bitcoin/bitcoin/blob/master/src/bitcoind.cpp#L116

(fixes #13004)

Tree-SHA512: 24ae460d9d97130a063f7bf7fa6da1e6cc46643a94ea0827aa64d0f4a80647e5e7394695b24ea0f49a147a1fa07329659d224f04511fc24b97a9869d1c29b890

Backport of Core PR13055
https://github.com/bitcoin/bitcoin/pull/13055/

Depends on D4511

Test Plan:

make check
./bitcoin-qt

Verify nothing is being output to the console.

Reviewers: deadalnix, Fabien, jasonbcox, O1 Bitcoin ABC, #bitcoin_abc

Reviewed By: deadalnix, O1 Bitcoin ABC, #bitcoin_abc

Differential Revision: https://reviews.bitcoinabc.org/D4514