Require alsa only with --enable-client

Hey guys,

the alsa libraries/header seem to be required only when configured with
--enable-client so I wrote a patch to make configure respect it.

--
Regards,
Christian Ruppert

From 53683cc75ba092799f856f710cb45b2aacfb6123 Mon Sep 17 00:00:00 2001
From: Christian Ruppert <idl0r@gentoo.org>
Date: Sun, 3 Nov 2013 18:36:26 +0100
Subject: [PATCH] Require alsa only with --enable-client
Fix snappy detection with newer spice-gtk

It was renamed to spicy-screenshot
Add .version to EXTRA_DIST

Newer versions of git-version-gen document that it should be done, and
builddir != srcdir builds are broken if it's not present in the tarball as
we'd attempt to generate this file in the read-only source directory (if
the source dir is read-only)
Update git-version-gen to latest version

Pick the latest git-version-gen version from
http://git.savannah.gnu.org/cgit/gnulib.git/plain/build-aux/git-version-gen
Add red_time.h to Makefile.am

This file was added in bc50ff076 a few months ago, but is not listed
in Makefile.am, and thus not part of tarballs. However, it's being included
from other C files, so not having it causes compilation breakage.
Remove empty red_time.c
Use TLS version 1.0 or better

When creating a TLS socket, both spice-server and spice-gtk currently
call SSL_CTX_new(TLSv1_method()). The TLSv1_method() function set the
protocol version to TLS 1.0 exclusively. The correct way to support
multiple protocol versions is to call SSLv23_method() in spite of its
scary name. This method will enable all SSL/TLS protocol versions. The
protocol suite may be further narrowed down by setting respective
SSL_OP_NO_<version_code> options of SSL context.  This possibility is
used in this patch in order to block use of SSLv3 that is enabled by
default in openssl for client sockets as of now but spice has never used
it.
Revise the spice client and server to use the new snd_codec functions in spice-common.

This makes celt optional, and paves the way to readily add additional codecs.

Signed-off-by: Jeremy White <jwhite@codeweavers.com>
Add support for the Opus codec

Signed-off-by: Jeremy White <jwhite@codeweavers.com>
Fix typo; sampel --> sample

Signed-off-by: Jeremy White <jwhite@codeweavers.com>
tests: Remove unused variables

coverity spotted some variables that were declared but not used in
server/tests
tests: Avoid malloc failures

test-display-streaming is calling malloc() without checking its return
value. Coverity warns about this. This commit switches to g_malloc() to
sidestep this warning (g_malloc() never returns NULL but aborts instead).