hal: update combo device handling

If the wired headset/headphone/line devices are handled by
a different backend than speaker/earpiece devices, the combo
devices such as speaker+headphones can be split into individual
devices and enabled/disabled independently.

Conflicts:
	hal/msm8916/platform.c
	hal/msm8974/platform.c

Change-Id: I30e90f398ef204d106b5d8dac8fba166583bdbc8
diff --git a/hal/msm8960/platform.c b/hal/msm8960/platform.c
index e32a73d..48470b9 100644
--- a/hal/msm8960/platform.c
+++ b/hal/msm8960/platform.c
@@ -1080,8 +1080,9 @@
     return -ENOSYS;
 }
 
-int platform_set_snd_device_backend(snd_device_t snd_device __unused,
-                                    const char * backend __unused)
+int platform_set_snd_device_backend(snd_device_t device __unused,
+                                    const char *backend __unused,
+                                    const char *hw_interface __unused)
 {
     return -ENOSYS;
 }
@@ -1210,4 +1211,16 @@
 int platform_spkr_prot_is_wsa_analog_mode(void *adev __unused)
 {
     return 0;
+bool platform_can_split_snd_device(void *platform __unused,
+                                   snd_device_t in_snd_device __unused,
+                                   int *num_devices __unused,
+                                   snd_device_t *out_snd_devices __unused)
+{
+    return false;
+}
+
+bool platform_check_backends_match(snd_device_t snd_device1 __unused,
+                                   snd_device_t snd_device2 __unused)
+{
+    return true;
 }