Follow-up to r1549924:  Simplify code.

* subversion/libsvn_fs_fs/index.c
  (index_create): Exploit the fact that svn_io_remove_file2 already
                  handles the r/o and n/a cases.

git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1553045 13f79535-47bb-0310-9956-ffa450edef68