net: http: Add error status string to HTTP server error

Add status error string when sending a error message from
HTTP server to client as described in RFC 2616 ch 6.1.
Previously only error code was sent except for 400 (Bad Request).

This also fixes uninitialized memory access in error message.

Coverity-CID: 178792
Fixes #4782

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
2 files changed