fix(base): do not change the provided UUID

During boot dracut parses the provided UUID to lower case and thus starts an
endless loop wating for the devise to appear. The device is actually mapped
correctly by the kernel (which doesn't tweak the UUID) but because we are
waiting for a name with lower charachters the expeted device never appers which
drops us at the emergency shell leaving the system unbootable.
This happens especially on nfts/fat filesystems because technically those don't
have a UUID but searial numbers which are used by the linux tools as UUID.

modules.d/99base/dracut-lib.sh

@@ -594,10 +594,10 @@ label_uuid_to_dev() {
             echo "/dev/disk/by-partlabel/$(echo "${_dev#PARTLABEL=}" | sed 's,/,\\x2f,g;s, ,\\x20,g')"
             ;;
         UUID=*)
-            echo "/dev/disk/by-uuid/$(echo "${_dev#UUID=}" | tr "[:upper:]" "[:lower:]")"
+            echo "/dev/disk/by-uuid/${_dev#UUID=}"
             ;;
         PARTUUID=*)
-            echo "/dev/disk/by-partuuid/$(echo "${_dev#PARTUUID=}" | tr "[:upper:]" "[:lower:]")"
+            echo "/dev/disk/by-partuuid/${_dev#PARTUUID=}"
             ;;
         *)
             echo "$_dev"