linux-yocto: Replace branch names in custom kernel recipes

Rename Kernel branches for linux-yocto-custom-rt:
- from "lsi_rt_axm55xx" to "standard/preempt-rt/lsi/axm55xx"
- from "lsi_rt_acp34xx" to "standard/preempt-rt/lsi/acp34xx"

Signed-off-by: Paul Butler <paul.butler@windriver.com>
axm5500sim: Corrected file name axm5500sim.inc

Signed-off-by: Paul Butler <paul.butler@windriver.com>
README: Updating with additional machine info

Signed-off-by: Paul Butler <paul.butler@windriver.com>
linux-yocto: Recipe updates to use kernel meta branch cfg/scc fragments

Modified recipes to use "meta" branch for kernel build
Removed defconfigs
Update Serial Console settings for axm5500sim

Signed-off-by: David Mercado <david.mercado@windriver.com>
Signed-off-by: Paul Butler <paul.butler@windriver.com>
u-boot-lsi: Add recipes-bsp/u-boot recipes for u-boot-lsi build

Add initial recipe for u-boot-lsi which will fetch a specific
u-boot version optimized for axm5500sim and other LSI machines.
Adapt axm5500sim conf machine to use u-boot-lsi as bootloader.

Signed-off-by: Paul Butler <paul.butler@windriver.com>
linux-yocto: Recipe updates for 7.8.1.7 Kernel tag

Updates to custom build recipes for 7.8.1.7 tag
Removed unnecessary inc files that only had a branch name
Updated defconfigs for 7.8.1.7 kernel tag

Signed-off-by: Paul Butler <paul.butler@windriver.com>
linux-yocto: Recipe updates for 7.8.1.8 Kernel tag

- Updates to custom build recipes for 7.8.1.8 kernel tag.
- Removed ssh protocol access to github. Users without github accounts
and/or access to private groups should be able to build now.

Signed-off-by: Paul Butler <paul.butler@windriver.com>
u-boot-lsi: Update SRCREV to tag 5.8.1.10

Signed-off-by: Paul Butler <paul.butler@windriver.com>
core-image-tiny: Add receipe for new rootfs image type

Add receipe for for core-image-tiny ROOTFS type and related packagegroup
receipes: packagegroup-core-tiny-boot.bb and packagegroup-core-tiny.bb.notused

Update conf/layer.conf:
- Add "core" to the list of configured layers (BBFILE_COLLECTIONS)
- Define the parent directory of the OpenEmbedded Core Metadata layer
(COREBASE)
- Define the list of recipes that are completely stable and will never
change (SIGGEN_EXCLUDERECIPES_ABISAFE)

Signed-off-by: Paul Butler <paul.butler@windriver.com>
axm5500: adding support for new machine type

- Add new machine configuration file for axm5500
- Add new u-boot recipe for emulation
The new machine type (axm5500) provides support for building
u-boot for both the emulation and asic flavors. The u-boot.bin
and u-boot-spl.bin images for both emulation and asic versions
are generated.
- Update SRCREV for u-boot-lsi to tag 5.8.1.12
- Define compatible machines: axm5500sim, axm5500, elpaso (acp34xx)
- Update SRCREV for linux-yocto-custom-rt to 7.8.1.9
- Add standard and preemt-rt defconfig files for axm5500 machine

Signed-off-by: Paul Butler <paul.butler@windriver.com>