update meta-swupd to current master

[pohly]

This brings in several enhancements:

• Incremental builds even when starting from a clean build environment (reduces size of swupd repo and speeds up builds).
• Significant performance improvements.

[pohly]

Once this is merged, I also have some more commits for meta-ostro which then complete the current set of swupd improvements. However, I think this PR will already work by itself, because the commits in meta-ostro just clean up a few things.

[pohly]

@mythi Test results are almost clean, only Edison failed for some (unrelated?) reasons. Looks like the device became unavailable while testing (ssh connection errors).

Shall we wait for a retest or just merge?

[pohly]

retest this please

At least retesting only takes one hour for building now ;-}

[pohly]

@mythi @incandescant: all tests clean - let's merge the update meta-swupd into Ostro.

[mythi]

@pohly thanks a lot!