Doxyfile: Disable case-sensitive filenames

In order to be convertable to sphinx, the filenames of the documentation
need to be lowercase to match the lowercase ids used in sphinx.

Change-Id: Ie28c08313c44665590f8bc354cde9a94499d47ea

doxyfile

@@ -514,7 +514,7 @@ INTERNAL_DOCS          = YES
 # and Mac users are advised to set this option to NO.
 # The default value is: system dependent.
 
-CASE_SENSE_NAMES       = YES
+CASE_SENSE_NAMES       = NO
 
 # If the HIDE_SCOPE_NAMES tag is set to NO then doxygen will show members with
 # their full class and namespace scopes in the documentation. If set to YES, the