target/hexagon: prepare input for the idef-parser

Introduce infrastructure necessary to produce a file suitable for being
parsed by the idef-parser. A build option is also added to fully disable
the output of idef-parser, which is useful for debugging.

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-8-anjo@rev.ng>

target/hexagon/idef-parser/prepare

@@ -0,0 +1,24 @@
+#!/bin/bash
+
+#
+#  Copyright(c) 2019-2021 rev.ng Labs Srl. All Rights Reserved.
+#
+#  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; either version 2 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, see <http://www.gnu.org/licenses/>.
+#
+
+set -e
+set -o pipefail
+
+# Run the preprocessor and drop comments
+cpp "$@"