wic: Add argument --hidden to default imager

Add argument --hidden to avoid MS Windows prompting to format
partition after flashing to a USB stick, SD card on another media.
Set Bit 0 (RequiredPartition) to mark that the partition is
required for the platform to function on GUID Partition Table
(GPT).

The new argument simplifies setting RequiredPartition on GPT
through a WKS file and the default imager plugin. Otherwise,
without this feature, to achieve the same result a new imager
plugin has to be implemented and set in WIC_CREATE_EXTRA_ARGS.

(From OE-Core rev: 7a111ff58d7390b79e2e63c8059f6c25f40f8977)

Signed-off-by: Leon Anavi <leon.anavi@konsulko.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

scripts/lib/wic/plugins/imager/direct.py

@@ -605,6 +605,13 @@ class PartitionedImage():
                                 (self.path, part.num, part.system_id),
                                 self.native_sysroot)
 
+            if part.hidden and self.ptable_format == "gpt":
+                logger.debug("Set hidden attribute for partition '%s' on disk '%s'",
+                             part.num, self.path)
+                exec_native_cmd("sfdisk --part-attrs %s %s RequiredPartition" % \
+                                (self.path, part.num),
+                                self.native_sysroot)
+
     def cleanup(self):
         pass