Enable the use of IOmxStore service

Test: Manual use of Camera app
Test: lshal shows IOmxStore

Bug: 37657124
Bug: 37726880
Change-Id: I5459d992c2feb14bd26765673864e583d48e3ba4

private/hwservice_contexts

@@ -22,6 +22,7 @@ android.hardware.ir::IConsumerIr                                u:object_r:hal_i
 android.hardware.keymaster::IKeymasterDevice                    u:object_r:hal_keymaster_hwservice:s0
 android.hardware.light::ILight                                  u:object_r:hal_light_hwservice:s0
 android.hardware.media.omx::IOmx                                u:object_r:hal_omx_hwservice:s0
+android.hardware.media.omx::IOmxStore                           u:object_r:hal_omx_hwservice:s0
 android.hardware.memtrack::IMemtrack                            u:object_r:hal_memtrack_hwservice:s0
 android.hardware.nfc::INfc                                      u:object_r:hal_nfc_hwservice:s0
 android.hardware.power::IPower                                  u:object_r:hal_power_hwservice:s0