Change directory structure to align with Atmel softpack

This way we can easily check with 'diff' for differences in our code and
Atmel softpack.  Also, this layout is more suitable for building various
different firmware images (e.g. factory-test, dfu-loader, main
application) for a variety of different boards (simtrace, owhw, qmod).

firmware/libcommon/source/iso7816_fidi.c

@@ -0,0 +1,64 @@
+/* ISO7816-3 Fi/Di tables + computation */
+/* (C) 2010-2015 by Harald Welte <hwelte@hmw-consulting.de>
+ *
+ *  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, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+#include <stdint.h>
+#include <errno.h>
+
+#include "utils.h"
+#include "iso7816_fidi.h"
+
+/* Table 7 of ISO 7816-3:2006 */
+static const uint16_t fi_table[] = {
+	372, 372, 558, 744, 1116, 1488, 1860, 0,
+	0, 512, 768, 1024, 1536, 2048, 0, 0
+};
+
+/* Table 8 from ISO 7816-3:2006 */
+static const uint8_t di_table[] = {
+	0, 1, 2, 4, 8, 16, 32, 64,
+	12, 20, 2, 4, 8, 16, 32, 64,
+};
+
+/* compute the F/D ratio based on Fi and Di values */
+int compute_fidi_ratio(uint8_t fi, uint8_t di)
+{
+	uint16_t f, d;
+	int ret;
+
+	if (fi >= ARRAY_SIZE(fi_table) ||
+	    di >= ARRAY_SIZE(di_table))
+		return -EINVAL;
+
+	f = fi_table[fi];
+	if (f == 0)
+		return -EINVAL;
+
+	d = di_table[di];
+	if (d == 0)
+		return -EINVAL;
+
+	/* See table 7 of ISO 7816-3: From 1000 on we divide by 1/d,
+	 * which equals a multiplication by d */
+	if (di < 8)
+		ret = f / d;
+	else
+		ret = f * d;
+
+	return ret;
+}