Revert "rpmsg: core: add support to power domains for devices"

This reverts commit 1ed3a930 which is
commit fe782aff upstream

Rafael reports that this patch causes problems:
	> -rc2 looks good. There is a problem on dragonboard during boot that was
	> introduced in v4.14.71 that I didn't notice last week. We'll bisect it
	> and report back later this week. dragonboard on the other branches (4.9,
	> 4.18, mainline) looks fine.

	As Dan pointed out, during validation, we have bisected this issue on
	a dragonboard 410c (can't find root device) to the following commit
	for v4.14:

	[1ed3a930] rpmsg: core: add support to power domains for devices

	There is an on-going discussion on "[PATCH] rpmsg: core: add support
	to power domains for devices" about this patch having other
	dependencies and breaking something else on v4.14 as well.

so drop it.
Reported-by: Rafael Tinoco <rafael.tinoco@linaro.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/rpmsg/rpmsg_core.c

@@ -23,7 +23,6 @@
 #include <linux/module.h>
 #include <linux/rpmsg.h>
 #include <linux/of_device.h>
-#include <linux/pm_domain.h>
 #include <linux/slab.h>
 
 #include "rpmsg_internal.h"
@@ -419,10 +418,6 @@ static int rpmsg_dev_probe(struct device *dev)
 	struct rpmsg_endpoint *ept = NULL;
 	int err;
 
-	err = dev_pm_domain_attach(dev, true);
-	if (err)
-		goto out;
-
 	if (rpdrv->callback) {
 		strncpy(chinfo.name, rpdev->id.name, RPMSG_NAME_SIZE);
 		chinfo.src = rpdev->src;
@@ -464,8 +459,6 @@ static int rpmsg_dev_remove(struct device *dev)
 
 	rpdrv->remove(rpdev);
 
-	dev_pm_domain_detach(dev, true);
-
 	if (rpdev->ept)
 		rpmsg_destroy_ept(rpdev->ept);