KNOWN_BUGS: Build with staticly built dependency

I rewrote the item 5.4 to be more generic about static dependencies.

docs/KNOWN_BUGS

@@ -48,7 +48,7 @@ problems may have been fixed or changed somewhat since this was written!
  5. Build and portability issues
  5.2 curl-config --libs contains private details
  5.3 curl compiled on OSX 10.13 failed to run on OSX 10.10
- 5.4 Cannot compile against a static build of OpenLDAP
+ 5.4 Build with staticly built dependency
  5.5 can't handle Unicode arguments in Windows
  5.6 cmake support gaps
  5.7 Visual Studio project gaps
@@ -355,9 +355,27 @@ problems may have been fixed or changed somewhat since this was written!
 
  See https://github.com/curl/curl/issues/2905
 
-5.4 Cannot compile against a static build of OpenLDAP
+5.4 Build with staticly built dependency
 
- See https://github.com/curl/curl/issues/2367
+ The build scripts in curl (autotools, cmake and others) are primarily done to
+ work with shared/dynamic third party dependencies. When linking with shared
+ libraries, the depedency "chain" is handled automatically by the library
+ loader - on all modern systems.
+
+ If you instead link with a static library, we need to provide all the
+ dependency libraries already at the link command line.
+
+ Figuring out all the dependency libraries for a given library is hard, as it
+ might also involve figuring out the dependencies of the dependencies and they
+ may vary between platforms and even change between versions.
+
+ When using static dependencies, the build scripts will mostly assume that
+ you, the user, will provide all the necessary additional dependency libraries
+ as additional arguments in the build. With configure, by setting LIBS/LDFLAGS
+ on the command line.
+
+ We welcome help to improve curl's ability to link with static libraries, but
+ it is likely a task that we can never fully support.
 
 5.5 can't handle Unicode arguments in Windows