Document default section and library configuration

It is talked around but not explicitly stated in one part of the
documentation that you should put library configuration lines at the
start of the configuration file.

CLA: trivial
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NBen Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/3959)

doc/man5/config.pod

@@ -64,7 +64,9 @@ file.
 To enable library configuration the default section needs to contain an
 appropriate line which points to the main configuration section. The default
 name is B<openssl_conf> which is used by the B<openssl> utility. Other
-applications may use an alternative name such as B<myapplicaton_conf>.
+applications may use an alternative name such as B<myapplication_conf>.
+All library configuration lines appear in the default section at the start
+of the configuration file.
 
 The configuration section should consist of a set of name value pairs which
 contain specific module configuration information. The B<name> represents
@@ -72,6 +74,7 @@ the name of the I<configuration module> the meaning of the B<value> is
 module specific: it may, for example, represent a further configuration
 section containing configuration module specific information. E.g.
 
+ # This must be in the default section
  openssl_conf = openssl_init
 
  [openssl_init]