Introduce soundtrigger HAL v3

This is the initial AIDL version of the soundtrigger HAL.
It is functionally equivalent to v2.4 (HIDL), but with a clean-up
interface that removes obsolete / legacy functionality and conforms to
AIDL style.

Test: Mocked the HAL and observed framework logs for basic use-cases.
Change-Id: I4525301ad1205cf41937a98b7b9f67f052cb5bd9
diff --git a/compatibility_matrices/compatibility_matrix.current.xml b/compatibility_matrices/compatibility_matrix.current.xml
index bb53654..6ea6783 100644
--- a/compatibility_matrices/compatibility_matrix.current.xml
+++ b/compatibility_matrices/compatibility_matrix.current.xml
@@ -527,6 +527,14 @@
             <instance>default</instance>
         </interface>
     </hal>
+    <hal format="aidl" optional="true">
+         <name>android.hardware.soundtrigger3</name>
+         <version>1</version>
+         <interface>
+             <name>ISoundTriggerHw</name>
+             <instance>default</instance>
+         </interface>
+    </hal>
     <hal format="hidl" optional="true">
         <name>android.hardware.tetheroffload.config</name>
         <version>1.0</version>