[ci skip] Fix 'sqlsrv' connect failure endless loop

Reported via the forums: http://forum.codeigniter.com/thread-61494.html
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 2d000ad..a0a54c3 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -18,6 +18,7 @@
 -  Fixed a bug (#2284) - :doc:`Database <database/index>` method ``protect_identifiers()`` breaks when :doc:`Query Builder <database/query_builder>` isn't enabled.
 -  Fixed a bug (#4052) - :doc:`Routing <general/routing>` with anonymous functions didn't work for routes that don't use regular expressions.
 -  Fixed a bug (#4056) - :doc:`Input Library <libraries/input>` method ``get_request_header()`` could not return a value unless ``request_headers()`` was called beforehand.
+-  Fixed a bug where the :doc:`Database Class <database/index>` entered an endless loop if it fails to connect with the 'sqlsrv' driver.
 
 Version 3.0.1
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