drm/xe: Fix uninitialized variables

Using uninitialized variables leads to undefined behavior.

Moreover, it causes the compiler to complain with:
../drivers/gpu/drm/xe/xe_vm.c:3265:40: error: variable 'vma' is uninitialized when used here [-Werror,-Wuninitialized]
../drivers/gpu/drm/xe/xe_rtp.c:118:36: error: variable 'i' is uninitialized when used here [-Werror,-Wuninitialized]
../drivers/gpu/drm/xe/xe_mocs.c:449:3: error: variable 'flags' is uninitialized when used here [-Werror,-Wuninitialized]
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://lore.kernel.org/r/20230523135020.345596-1-michal@hardline.plSigned-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/xe/xe_mocs.c

@@ -373,7 +373,7 @@ static const struct xe_mocs_entry mtl_mocs_desc[] = {
 static unsigned int get_mocs_settings(struct xe_device *xe,
 				      struct xe_mocs_info *info)
 {
-	unsigned int flags;
+	unsigned int flags = 0;
 
 	memset(info, 0, sizeof(struct xe_mocs_info));
 

drivers/gpu/drm/xe/xe_rtp.c

@@ -136,7 +136,7 @@ static bool rtp_process_one_sr(const struct xe_rtp_entry_sr *entry,
 	if (!rule_matches(xe, gt, hwe, entry->rules, entry->n_rules))
 		return false;
 
-	for (action = &entry->actions[0]; i < entry->n_actions; action++, i++) {
+	for (i = 0, action = &entry->actions[0]; i < entry->n_actions; action++, i++) {
 		if ((entry->flags & XE_RTP_ENTRY_FLAG_FOREACH_ENGINE) ||
 		    (action->flags & XE_RTP_ACTION_FLAG_ENGINE_BASE))
 			mmio_base = hwe->mmio_base;

drivers/gpu/drm/xe/xe_vm.c

@@ -3297,7 +3297,7 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
 		if (!vmas[i])
 			break;
 
-		list_for_each_entry_safe(vma, next, &vma->unbind_link,
+		list_for_each_entry_safe(vma, next, &vmas[i]->unbind_link,
 					 unbind_link) {
 			list_del_init(&vma->unbind_link);
 			if (!vma->destroyed) {