Merge #16481: Trivial: add missing space

Summary:
16b3748189a300a32a3016c22b1dfdca13485bac Trivial: add missing space (David A. Harding)

Pull request description:

A space was lost when the `PACKAGE_NAME` variable was introduced at https://github.com/bitcoin/bitcoin/pull/16366/files#diff-6e30027c2045842fe842430d98d099fbR143 , e.g. when running `bitcoind -daemon` on Linux before this commit, I see `Bitcoin Coredaemon starting`.  This commit adds back the space.

ACKs for top commit:

fanquake:
  ACK 16b3748189a300a32a3016c22b1dfdca13485bac

Tree-SHA512: 3b0c5ed91838f0254b0aa064d1839f90fb64b2ade82bc3f6233d287b553528da5315017cb9a1d3f2b1882a010343b18a5308ae63ca4e3d47e83e8c5b532ddf5f

Test Plan:

ninja
./bitcoind -daemon

Verify output is Bitcoin ABC daemon starting

Reviewers: O1 Bitcoin ABC, #bitcoin_abc, jasonbcox

Reviewed By: O1 Bitcoin ABC, #bitcoin_abc, jasonbcox

Differential Revision: https://reviews.bitcoinabc.org/D6316