* modules/mappers/mod_rewrite.c: Enhance trace-level logging to log

* modules/mappers/mod_rewrite.c: Enhance trace-level logging to log
  line numbers accurately for C99 compilers, and remove odd/awkward
  double-parentheses using the rewritelog() macro.  For non-C99
  compilers do_rewritelog() will now be defined - but as a noop - if
  REWRITELOG_DISABLED is defined at compile time.

No functional change at runtime apart from the line numbers being
fixed.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1866894 13f79535-47bb-0310-9956-ffa450edef68