Fix incorrect min bit rate setting for AMR NB audio recording

Not sure why we did not do this the first day, and the min bit rate recording works just fine.

o related-to-bug: 5924354

Change-Id: I7b01703f84861df03caf7a1f9e538eab679056ee
diff --git a/media_profiles.xml b/media_profiles.xml
index 02058a5..ce6d7dd 100755
--- a/media_profiles.xml
+++ b/media_profiles.xml
@@ -367,7 +367,7 @@
         minChannels="1" maxChannels="1" />
 
     <AudioEncoderCap name="amrnb" enabled="true"
-        minBitRate="5525" maxBitRate="12200"
+        minBitRate="4750" maxBitRate="12200"
         minSampleRate="8000" maxSampleRate="8000"
         minChannels="1" maxChannels="1" />