dracut-module-setup: Fix DRM module inclusion test for hyper-v

We test if to include the drm module or not by testing if there are any
drm entry in sysfs. But there is an exception for hyper-v, DRM module
take care of hyperv's framebuffer driver as well but hyperv_fb will
not create any drm entry. So currently we got black screen on
hyperv guest.

Fix by detect hyperv's special entry as well.

Signed-off-by: Kairui Song <kasong@redhat.com>

dracut-module-setup.sh

@@ -20,7 +20,7 @@ check() {
 depends() {
     local _dep="base shutdown"
 
-    if [ -n "$( find /sys/devices -name drm )" ]; then
+    if [ -n "$( find /sys/devices -name drm )" ] || [ -d /sys/module/hyperv_fb ]; then
         _dep="$_dep drm"
     fi