uboot-layerscape: update PKG_HASH

uboot-layerscape: update PKG_HASH

The change of the PKG_VERSION caused the hash of the package to
change. This is because the PKG_VERSION is present in the
internal directory structure of the uboot-layerscape-21.08.tar.xz
archive.

i.e:
 # tar tf uboot-layerscape-21.08.tar.xz:

uboot-layerscape-21.08/
uboot-layerscape-21.08/.azure-pipelines.yml
uboot-layerscape-21.08/.checkpatch.conf
uboot-layerscape-21.08/.gitattributes
uboot-layerscape-21.08/.github/
[...]

vs.

 # tar tf uboot-layerscape-LSDK-21.08.tar.xz
uboot-layerscape-LSDK-21.08/
uboot-layerscape-LSDK-21.08/.azure-pipelines.yml
uboot-layerscape-LSDK-21.08/.checkpatch.conf
uboot-layerscape-LSDK-21.08/.gitattributes
uboot-layerscape-LSDK-21.08/.github/
[...]

the (file) content of both archives are otherwise the same.

The PKG_HASH was taken from the builder log:
| Hash of the local file uboot-layerscape-21.08.tar.xz does not match
|(file: 54909a98bdcc26c7f9b35b35fcae09b977ecbf044be7bffa6dad9306c47cccf6,
|requested: 874e871755ef84ebbf3[...]) - deleting download.

without this update, the uboot-layerscape-21.08 package would
always try to download (from git), repacked the archive and
reupload to sources.openwrt.org (~14 MiB saved).

Fixes: 038d5bdab117 ("layerscape: use semantic versions for LSDK")
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>