Replace regular ampersand in device titles with &

Using the regular ampersand in device titles causes problems with the
TWRP app.

Change-Id: I2d8ecf7fc63c7217b4da9eb7eaaf43f9a9045946
diff --git a/_devices/samsunggalaxys3att.markdown b/_devices/samsunggalaxys3att.markdown
index 67f24cc..2587d04 100644
--- a/_devices/samsunggalaxys3att.markdown
+++ b/_devices/samsunggalaxys3att.markdown
@@ -1,6 +1,6 @@
 ---
 layout: device
-title:  "Samsung Galaxy S3 AT&T"
+title:  "Samsung Galaxy S3 AT&T"
 codename: d2att
 downloadfolder: d2att
 oldurl: http://teamw.in/project/twrp2/104