Remove ENABLE_WALLET from libbitcoin_server.a

Summary:
Backport of core PR14168.

Depends on D5054.

Test Plan:

ninja all check
make check

cmake -GNinja .. -DBUILD_BITCOIN_WALLET=OFF
ninja all check

../configure --disable-wallet
make check

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D5058