NetworkPkg/HttpDxe: Strip square brackets in IPv6 expressed HostName.

NetworkPkg/HttpDxe: Strip square brackets in IPv6 expressed HostName.

*v2: Optimize the patch by calculating AsciiStrSize() only once.

In URI, the colon (:) is used to terminate the HostName path before
a port number. However, if HostName is expressed as IPv6 format, colon
characters in IPv6 addresses will conflict with the colon before port
number. To alleviate this conflict in URI, the IPv6 expressed HostName
are enclosed in square brackets ([]). To record the real IPv6 HostName,
square brackets should be stripped.

Cc: Ye Ting <ting.ye@intel.com>
Cc: Fu Siyuan <siyuan.fu@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Wu Jiaxin <jiaxin.wu@intel.com>
Reviewed-by: Fu Siyuan <siyuan.fu@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>