Whitespace: Replace tab character in license text with two spaces

For whatever reason tabs got inserted in the license header text.
Remove one occurrence of that with the following command [1].

    $ git grep -l 'MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.'$'\t' | xargs sed -i 's,MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.[        ]*,MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\ \ ,'

[1] http://sed.sourceforge.net/grabbag/tutorials/sedfaq.txt

Change-Id: Iaf4ed32c32600c3b23c08f8754815b959b304882
Signed-off-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-on: http://review.coreboot.org/2460
Tested-by: build bot (Jenkins)
Reviewed-by: Jens Rottmann <JRottmann@LiPPERTembedded.de>
Reviewed-by: Cristian Măgherușan-Stanciu <cristi.magherusan@gmail.com>
diff --git a/src/drivers/spi/stmicro.c b/src/drivers/spi/stmicro.c
index b741d30..9aa31cf 100644
--- a/src/drivers/spi/stmicro.c
+++ b/src/drivers/spi/stmicro.c
@@ -18,7 +18,7 @@
  *
  * 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
+ * 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