Remove useMasterVolume default

useMasterVolume being set to true was inherited from Nexus Q. It
requires HAL support to actually use, so shouldn't be the default
for most devices. Instead, on ATV devices all streams are aliased
to media.

Change-Id: I03bd82b2a180dda7977fbb3282971fd7a2f3a7fc
diff --git a/overlay/frameworks/base/core/res/res/values/config.xml b/overlay/frameworks/base/core/res/res/values/config.xml
index 69c0447..03f3c5b 100644
--- a/overlay/frameworks/base/core/res/res/values/config.xml
+++ b/overlay/frameworks/base/core/res/res/values/config.xml
@@ -15,11 +15,6 @@
 -->
 
 <resources>
-
-    <!-- Flag indicating that the media framework should allow changing
-         master volume stream and nothing else . -->
-    <bool name="config_useMasterVolume">true</bool>
-
     <!-- Flag indicating that the media framework should support playing of sounds on volume
          key usage.  This adds noticeable additional overhead to volume key processing, so
          is disableable for products for which it is irrelevant. -->