compatibility_matrix: restore P graphics.composer
am: 7986bd66ad

Change-Id: Ib97064a87146dbee852a8739165aeb9db2e5ab75
diff --git a/compatibility_matrices/compatibility_matrix.3.xml b/compatibility_matrices/compatibility_matrix.3.xml
index 4cb3776..e13d293 100644
--- a/compatibility_matrices/compatibility_matrix.3.xml
+++ b/compatibility_matrices/compatibility_matrix.3.xml
@@ -193,7 +193,7 @@
     </hal>
     <hal format="hidl" optional="false">
         <name>android.hardware.graphics.composer</name>
-        <version>2.1-3</version>
+        <version>2.1-2</version>
         <interface>
             <name>IComposer</name>
             <instance>default</instance>