[CVE-2019-18348] Disallow control characters in hostnames in http.client

[CVE-2019-18348] Disallow control characters in hostnames in http.client

An issue was discovered in urllib2 in Python 2.x through 2.7.17
and urllib in Python 3.x through 3.8.0. CRLF injection
is possible if the attacker controls a url parameter,
as demonstrated by the first argument to urllib.request.
urlopen with \r\n (specifically in the host component
of a URL) followed by an HTTP header.

Change-Id: I733ec1d4986c5b638865ed70530f70a3ea0bd524
Signed-off-by: JinWang An <jinwang.an@samsung.com>