misc: fastrpc: Rename audio protection domain to root

The AUDIO_PD will be done via static pd, so the proper name here is
actually ROOT_PD.

Co-developed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20221125071405.148786-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/fastrpc.c

@@ -83,7 +83,7 @@
 #define FASTRPC_RMID_INIT_MEM_UNMAP    11
 
 /* Protection Domain(PD) ids */
-#define AUDIO_PD	(0) /* also GUEST_OS PD? */
+#define ROOT_PD		(0)
 #define USER_PD		(1)
 #define SENSORS_PD	(2)
 
@@ -1886,7 +1886,7 @@ static long fastrpc_device_ioctl(struct file *file, unsigned int cmd,
 		err = fastrpc_invoke(fl, argp);
 		break;
 	case FASTRPC_IOCTL_INIT_ATTACH:
-		err = fastrpc_init_attach(fl, AUDIO_PD);
+		err = fastrpc_init_attach(fl, ROOT_PD);
 		break;
 	case FASTRPC_IOCTL_INIT_ATTACH_SNS:
 		err = fastrpc_init_attach(fl, SENSORS_PD);