Revert "package/boost: bump to version 1.58.0"

This reverts commit 25655021fb66f58afe4966face0afdda1e7be65a.

Boost 1.58.0 breaks the build, trying to pass -m32 to compilers that
do not support it:

  http://autobuild.buildroot.org/results/66c/66c3a868816dfe4bd4d0ffafec6988fd87a2c058/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/boost/boost.hash

@@ -1,3 +1,3 @@
-# From http://sourceforge.net/projects/boost/files/boost/1.58.0/
-md5	b8839650e61e9c1c0a89f371dd475546	boost_1_58_0.tar.bz2
-sha1	2fc96c1651ac6fe9859b678b165bd78dc211e881	boost_1_58_0.tar.bz2
+# From http://sourceforge.net/projects/boost/files/boost/1.57.0/
+md5	1be49befbdd9a5ce9def2983ba3e7b76	boost_1_57_0.tar.bz2
+sha1	e151557ae47afd1b43dc3fac46f8b04a8fe51c12	boost_1_57_0.tar.bz2

package/boost/boost.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-BOOST_VERSION = 1.58.0
+BOOST_VERSION = 1.57.0
 BOOST_SOURCE = boost_$(subst .,_,$(BOOST_VERSION)).tar.bz2
 BOOST_SITE = http://downloads.sourceforge.net/project/boost/boost/$(BOOST_VERSION)
 BOOST_INSTALL_STAGING = YES