cleanup and document LEDE project Kernel patches in a "saner" way

lede.kernel.patches.txt

# Proposal for cleanup/recommended patch naming of LEDE Kernel changes
Target: Kernel 4.6(?)

current situation:
- 0xx-099 : 
- 1xx-199 : 
- 2xx-299 :
- 3xx-399 : mips
- 4xx-499 : mtd
- 5xx-599 : fs (yaffs,lzma)
- 6xx- : netfilter
- 7xx-799 : net/phy subsystem
- 8xx-
- 9xx- :

Current issues:
- no documentation (but git history) of package modification or
package/patch dependencies (see list w. current 4.4 examples)

Goals:
- see if patch is LEDE specific or not
- make kernel porting faster
- make commit logs more visible


proposed structure inside patch files:
* information on package interaction
* section: backport/hack/lede specific (not upstreamable)
* upstream status (in patch)

- 0xx-099 : modifications - size hacks? (modularization)
- 1xx-199 : additions (new modules/config symbols)
- 2xx-299 : kernel mods due to musl/libc
- 3xx-399 : 
- 4xx-499 : subsystem/maintainer/contributor1
- 5xx-599 : subsystem2/contributor2
- 6xx- : 
- 7xx-799 : 
- 8xx- : 
- 9xx- : mixed contribs

proposed file name scheme:
001-(upstream|backport_v??|projectname)-SUBSYS/ARCH-TEXT

proposed naming of patch series: 
001-001-(upstream|backport_v??)-SUBSYS/ARCH-TEXT
001-002-(upstream|backport_v??)-SUBSYS/ARCH-TEXT

example issues in current 4.4:
214 - spidev / musl change
251 - sound module building
259 - regmap module
270 - uapi/musl
271 - uapi/musl
272 - uapi/musl
700 - net/phy patches (switch.h header)
904 - debloat dma
910 kobject (some package require this iirc)
911 kobject uevent
-> list was created by trying out Kernel 4.6 on x86/VM

- fq_codel 03x and 660
- 3xx : MIPS/arc/ppc/MIPS
- 257/255 mac80211 kconfig

# Proposal of package patch naming

001-099: build system modification; ex: configure.ac (or configure), Makefile patches
100-199: source code modification - compatibility musl changes (headers ...)
200-299: source code modifications (size reductions, stripping of code)

## Naming scheme:
0xx-UPSTREAM|project|source-patchname.patch