camera: Add aconfig flag for session hal buffer manager

Bug: 311263114

Test: builds

Change-Id: I4b1e49bde39233c73a4b3dbcfedff221627b80d6
Signed-off-by: Jayant Chowdhary <jchowdhary@google.com>
diff --git a/camera/camera_platform.aconfig b/camera/camera_platform.aconfig
index 5386e69..f320d34 100644
--- a/camera/camera_platform.aconfig
+++ b/camera/camera_platform.aconfig
@@ -35,3 +35,9 @@
      bug: "307409002"
 }
 
+flag {
+     namespace: "camera_platform"
+     name: "session_hal_buf_manager"
+     description: "Enable or disable HAL buffer manager as requested by the camera HAL"
+     bug: "311263114"
+}
\ No newline at end of file