Fix a problem in windows build introduced a few csets ago (in

"Merge Monty's fixes from main into release branch" .. cset):
- mysql_get_server_name() is a new client API function and so should
  be exported from libmysql[d].

libmysql/libmysql.def:
  mysql_get_server_name() is a new client API function and so should
  be exported from libmysql[d].
libmysqld/libmysqld.def:
  mysql_get_server_name() is a new client API function and so should
  be exported from libmysql[d].

libmysql/libmysql.def

@@ -151,3 +151,4 @@ EXPORTS
 	mysql_get_character_set_info
 	get_defaults_options
 	modify_defaults_file
+	mysql_get_server_name

libmysqld/libmysqld.def

@@ -108,3 +108,4 @@ EXPORTS
 	mysql_stmt_attr_get
 	mysql_stmt_attr_set
 	mysql_stmt_field_count
+	mysql_get_server_name