MBR: fix compatibility with libparted >= 3.6

With parted 3.6 a check was implemented that allows setting the LBA flag
only for msdos partitions that support it (i.e. all fat types, DOS_EXT and EXT_LBA).

To fix the issue only set the flag when it is supported.

embdgen-core/src/embdgen/core/label/BaseLabel.py

@@ -63,7 +63,7 @@ def add_partition(self, part: PartitionRegion, logical: bool=False, boot_partiti
         )
         if boot_partition:
             partition.setFlag(parted.PARTITION_BOOT)
-        if self._label_type == "msdos":
+        if self._label_type == "msdos" and partition.isFlagAvailable(parted.PARTITION_LBA):
             partition.setFlag(parted.PARTITION_LBA)
         if part.fstype == "esp":
             partition.setFlag(parted.PARTITION_ESP)