Added multilib parse-config which will handle packages flagged with MULTILIB

Improved multilib parse-config first to cleanup and then injecting architecture specific compiler flags

Note: Currently only x86-64 is implemented but others will be added as soon
      as they are tested properly!

Improved readability of multilib parse-config replacing 'expr' and backtick notation

multilib: fixed parse-config to backup arch_target and restore it after compiling

lib/multilib/parse-config

@@ -0,0 +1,55 @@
+# --- SDE-COPYRIGHT-NOTE-BEGIN ---
+# This copyright note is auto-generated by ./scripts/Create-CopyPatch.
+#
+# Filename: lib/multilib/parse-config
+# Copyright (C) 2008 - 2011 The OpenSDE Project
+#
+# More information can be found in the files COPYING and README.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; version 2 of the License. A copy of the
+# GNU General Public License can be found in the file COPYING.
+# --- SDE-COPYRIGHT-NOTE-END ---
+
+# Multilib helper functions
+#
+# arch_abis	A list of ABIs generated by architecture/$arch/parse-config
+#		with the default ABI as first element
+
+# function to set the abi taking buildloop as argument
+multilib_abi_loop() {
+	abi=$( echo "$arch_abis" | cut -d ' ' "-f$1" )
+	echo_status "Building multilib $pkg for $abi ABI"
+
+	# cleanup architecture specific compiler flags
+	var_remove_regex CC_WRAPPER_INSERT ' ' '\-m.*'
+	var_remove_regex CXX_WRAPPER_INSERT ' ' '\-m.*'
+
+	# inject architecture specific compiler flags
+	case "$arch" in
+		x86-64)
+			var_insert CC_WRAPPER_INSERT ' ' "-m$abi"
+			var_insert CXX_WRAPPER_INSERT ' ' "-m$abi"
+			;;
+	esac
+
+	# alter arch_target if we build 32bit
+	if [ "$abi" = "32" ]; then
+		# backup arch_target and restore it after compiling
+		hook_add postmake 9 "arch_target=$arch_target"
+		arch_target="$( echo $arch_target | arch2arch32 )"
+		echo_status "Setting arch_target to $arch_target"
+	fi
+
+	# set a proper arch_suffix for pkggetdir to set the right libdir
+	arch_suffix=$abi
+	set_confopt
+}
+
+if [ "$SDECFG_MULTILIB" == "1" ] && hasflag MULTILIB && ! atstage toolchain; then
+	echo_status "Enabling Multilib Support (selected ABIs: $arch_abis) (default: $SDECFG_ABI_DEFAULT)"
+
+	multilib_buildloops="$( echo $arch_abis | wc -w )"
+	buildloops="$multilib_buildloops"
+fi