bitbake-metadata2doc.py: append branch information to versions, if it exists

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
extract-bitbake-metadata.py: take machine and soc family into account when determining preferred providers

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
release-notes: remove linux-fslc section

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
release-notes/soc-pkg-optimization.inc use dashes instead of bullets

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
bitbake-metadata2doc.py: sort description lists

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
bitbake-metadata2doc.py: is_compatible_machine: return True when given falsy value for compatible_machine_re

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
bitbake-metadata2doc.py: work around the lack of layer information in write_fsl_community_bsp_supported_kernels

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
bitbake-metadata2doc.py: handle recipes that don't exist in the dumped metadata

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
extract-bitbake-metadata.py: rewritten

extract-bitbake-metadata.py has been rewritten using pieces of
Christopher Larson's bb tool (https://github.com/kergoth/bb), which is
more reliable and simpler than the precious approach.

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
bitbake-metadata2doc.sh: add u-boot to the list of recipes to query bitbake for

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
bitbake-metadata2doc.sh: abort on the first error

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
bitbake-metadata2doc.py: revamp bootloader stuff

Merge barebox and u-boot information into the same tables: one for
description (fsl-community-bsp-supported-bootloaders-descr.inc) and
another one to show the default bootloaders (and their respective
versions) for boards (bootloader-default.inc)

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
bitbake-metadata2doc.py: remove write_u_boot_default

It's not used anymore now that barebox and u-boot have been merged
into the same table.

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>
release-notes: update documentation according to the scripts status

Signed-off-by: Mario Domenech Goulart <mario@ossystems.com.br>