Provide system error messages instead of just OS/2 error codes for dynamic

linking errors. I don't particularly like using static char buffers like
this but ap_os_dso_error() doesn't take a pool.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@83192 13f79535-47bb-0310-9956-ffa450edef68