[isar-cip-core][PATCH] efibootguard-boot.py: update dtbs based on their deploydir subdir paths

["nicusor.huhulea@siemens.com" <nicusor.huhulea@siemens.com>]

This needs to be in sync with the isar image.bbclass changes where the dtbs are placed in
their corresponded image name subdirectories. 


    Signed-off-by: Nicusor Huhulea <nicusor.huhulea@siemens.com>

diff --git a/scripts/lib/wic/plugins/source/efibootguard-boot.py b/scripts/lib/wic/plugins/source/efibootguard-boot.py
index 4e3aefb..86e342c 100644
--- a/scripts/lib/wic/plugins/source/efibootguard-boot.py
+++ b/scripts/lib/wic/plugins/source/efibootguard-boot.py
@@ -181,6 +181,8 @@ class EfibootguardBootPlugin(SourcePlugin):
                                      deploy_dir, kernel_image, initrd_image,
                                      dtb_files, source_params):
         rootfs_path = rootfs_dir.get('ROOTFS_DIR')
+        image_basename = get_bitbake_var("IMAGE_BASENAME")
+        machine = get_bitbake_var("MACHINE")
         efiarch = get_bitbake_var("EFI_ARCH")
         if not efiarch:
             msger.error("Bitbake variable 'EFI_ARCH' not set, exiting\n")
@@ -210,8 +212,10 @@ class EfibootguardBootPlugin(SourcePlugin):
                 uefi_kernel_file=uefi_kernel_file)
         if dtb_files:
             for dtb in dtb_files:
-                cmd += ' -d {deploy_dir}/{dtb_file}'.format(
+                cmd += ' -d {deploy_dir}/{image_basename}-{machine}.dtbs/{dtb_file}'.format(
                     deploy_dir=deploy_dir,
+                    image_basename=image_basename,
+                    machine=machine,
                     dtb_file=os.path.basename(dtb))
         exec_cmd(cmd, as_shell=True)