DRTVWR-418: Backed out changeset f03df2b249d0: restore -quiet.

As of now, this fork requires Xcode 8, which introduces support for the -quiet
switch.

autobuild.xml

@@ -3328,6 +3328,7 @@
                 </array>
                 <key>options</key>
                 <array>
+                  <string>-quiet</string>
                   <string>-configuration</string>
                   <string>RelWithDebInfo</string>
                   <string>-project</string>
@@ -3359,6 +3360,7 @@
                 <string>xcodebuild</string>
                 <key>options</key>
                 <array>
+                  <string>-quiet</string>
                   <string>-configuration</string>
                   <string>RelWithDebInfo</string>
                   <string>-project</string>
@@ -3388,6 +3390,7 @@
                 </array>
                 <key>options</key>
                 <array>
+                  <string>-quiet</string>
                   <string>-configuration</string>
                   <string>Release</string>
                   <string>-project</string>
@@ -3419,6 +3422,7 @@
                 <string>xcodebuild</string>
                 <key>options</key>
                 <array>
+                  <string>-quiet</string>
                   <string>-configuration Release</string>
                   <string>-project SecondLife.xcodeproj</string>
                   <string>-DENABLE_SIGNING:BOOL=YES</string>