do_depmod: use $install_tree instead of hardcoding /lib/modules

dkms.in

@@ -348,12 +348,12 @@ do_depmod()
     else
         depmod -a "$1"
     fi
-    if [ -f /lib/modules/$1/modules.dep ] && [ ! -s /lib/modules/$1/modules.dep ]; then
+    if [ -f $install_tree/$1/modules.dep ] && [ ! -s $install_tree/$1/modules.dep ]; then
         # if modules.dep is empty, we just removed the last kernel module from
         # no longer installed kernel $1, so do not leave stale depmod files around
-        rm -fv /lib/modules/$1/modules.{alias,dep,devname,softdep,symbols,*.bin}
-        rmdir --ignore-fail-on-non-empty /lib/modules/$1
-        test -d /lib/modules/$1 || echo $"Removed /lib/modules/$1"
+        rm -fv $install_tree/$1/modules.{alias,dep,devname,softdep,symbols,*.bin}
+        rmdir --ignore-fail-on-non-empty $install_tree/$1
+        test -d $install_tree/$1 || echo $"removed directory $install_tree/$1"
     fi
 }