Change Details

``` Move some C/CXX FLAGS out of C/CXX. The remaining flags are host/SDK related, and will need some more thought. This is more correct in any case, and simplifies future changes. ``` Backport of core#29233. Depends on D17249.

``` Move some C/CXX FLAGS out of C/CXX. The remaining flags are host/SDK related, and will need some more thought. This is more correct in any case, and simplifies future changes. ``` Backport of [[https://github.com/bitcoin/bitcoin/pull/29233 | core#29233]]. Depends on D17249.

``` Move some C/CXX FLAGS out of C/CXX. The remaining flags are host/SDK related, and will need some more thought. This is more correct in any case, and simplifies future changes. ``` Backport of [[https://github.com/bitcoin/bitcoin/pull/29233 | core#29233]]. Depends on D17249.