Merge bitcoin/bitcoin#28231: doc: remove Fedora libdb4-*-devel install docs

11a499e doc: remove Fedora libdb4-*-devel install docs (fanquake)

Pull request description:

  These are no-longer installable on any recent Fedora (last working version was 32).
  Remove the install instructions, and consolidate this section to be the same as the
  Ubuntu & Debian BDB install instructions.

ACKs for top commit:
  MarcoFalke:
    lgtm ACK 11a499e

Tree-SHA512: 11e3c92d6dcf475a6f5529a2e41dc9f79eeae8f8d3600087ce5ae083264f999782a2c04a4c4c70073e96d4053daa23037a344224197ee5f15a3d635172c201e2

Author: fanquake

doc/build-unix.md

@@ -55,7 +55,7 @@ SQLite is required for the descriptor wallet:
     sudo apt install libsqlite3-dev
 
 Berkeley DB is only required for the legacy wallet. Ubuntu and Debian have their own `libdb-dev` and `libdb++-dev` packages,
-but these will install Berkeley DB 5.1 or later. This will break binary wallet compatibility with the distributed
+but these will install Berkeley DB 5.3 or later. This will break binary wallet compatibility with the distributed
 executables, which are based on BerkeleyDB 4.8. If you do not care about wallet compatibility, pass
 `--with-incompatible-bdb` to configure. Otherwise, you can build Berkeley DB [yourself](#berkeley-db).
 
@@ -111,11 +111,7 @@ SQLite is required for the descriptor wallet:
 
     sudo dnf install sqlite-devel
 
-Berkeley DB is required for the legacy wallet:
-
-    sudo dnf install libdb4-devel libdb4-cxx-devel
-
-Berkeley DB is only required for the legacy wallet. Newer Fedora releases have only `libdb-devel` and `libdb-cxx-devel` packages, but these will install
+Berkeley DB is only required for the legacy wallet. Fedora releases have only `libdb-devel` and `libdb-cxx-devel` packages, but these will install
 Berkeley DB 5.3 or later. This will break binary wallet compatibility with the distributed executables, which
 are based on Berkeley DB 4.8. If you do not care about wallet compatibility,
 pass `--with-incompatible-bdb` to configure. Otherwise, you can build Berkeley DB [yourself](#berkeley-db).