Move back to 4.19.x because of perf issues with 4.20

- linux-4.20.2-seblu
- linux-4.9.150-seblu

- Only build when PKGBUILD are changed
- Remove not needed chmod

No more conflict between split packages. Both are allowed on the same system.

- Only when PKGBUILD changes
- Remove debug messages

- Introduce linux-seblu-4.9-meta to track 4.9 releases
- Add kernel 4.20

linux-4.18.20-seblu
linux-4.9.146-seblu

Bump to 4.18.1 and 4.9.120

Conflict older kenrnel because of CVE-2018-3620 & CVE-2018-3646

- Bump main to 4.18.0

Older kernel are conflicted because of CVE-2018-5390

- Add linux-4.17.0-seblu

- linux-4.16.0-seblu
- linux-4.9.92-seblu

- linux 4.9.79

Release of linux 4.15

- linux-4.14.15-seblu
- linux-4.9.78-seblu

4.12.5 is unpatched too

4.14.0 is unpatched too

- Remove unpatched kernel (related to meltdown and spectre)