Check to make sure that the file name is not NULL before passing it to the

strncmp() function.  At least on NetWare this prevents the strncmp() function
from faulting and also brings the code into sync with similar checks for a NULL
file name before calling strncmp() in other areas of this file.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@101361 13f79535-47bb-0310-9956-ffa450edef68