Replace two bad sprintf() calls with ap_snprintf() variants in mod_rewrite.

The sprintf()'s were incorrectly introduced recently because Ralf didn't
recognize that although the ap_psprintf() needs a pool (which is not available
at the particular place in mod_rewrite) we also have the non-pool based more
secure ap_snprintf() (which is now used).

Thanks to Marc for complaining and giving the hint to ap_snprintf().


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@81517 13f79535-47bb-0310-9956-ffa450edef68