[LEDE-DEV] [RFC] brcm47xx: bump kernel to 4.4

[p.wassi at gmx.at]

Ok, here's some news on this topic.
I've built some images for WRT54GL to test, here come the results:

-) Builtbot's image: does NOT boot (as expected)
-) Local image without KALLSYMS: works fine
-) Local image with KALLSYMS: does NOT boot (which is unexpected,
       as such an image booted without issues back in June)

Here are my vmlinux.lzma sizes:
1140026 bytes - without KALLSYMS - works
1229451 bytes - with KALLSYMS - does not work

To further investigate where the 'magic border' is, (assuming it really is dependant on
the vmlinux.lzma size), I've disabled KALLSYMS and introduced a new char array in the
kernel with random contents. I could more or less define what size the kernel should have.
Here are the results:
size     | status
1140026  |  Ok    <= this is the untouched kernel without KALLSYMS 
1195918  |  Ok
1206415  |  Ok
1227370  |  Ok
1229451  |  FAIL  <= this is the untouched kernel with KALLSYMS enabled
1237671  |  Ok
1279313  |  Ok

So there must be more than just the bare vmlinux-size.

Best regards,
P. Wassi