docs: replace `FOO by :term:FOO` where possible

If a variable has a glossary entry and some rST files write about those
variables, it's better to point to the glossary entry instead of just
highlighting it by surrounding it with two tick quotes.

This was automated by the following python script:
"""
import re
from pathlib import Path

with open('objects.inv.txt', 'r') as f:
    objects = f.readlines()

with open('bitbake-objects.inv.txt', 'r') as f:
    objects = objects + f.readlines()

re_term = re.compile(r'variables.html#term-([A-Z_0-9]*)')
terms = []

for obj in objects:
    match = re_term.search(obj)
    if match and match.group(1):
        terms.append(match.group(1))

for rst in Path('.').rglob('*.rst'):
    with open(rst, 'r') as f:
        content = "".joing(f.readlines())
    for term in terms:
        content = re.sub(r'``({})``(?!.*\s*[~-]+)'.format(term), r':term:`\1`', content)

    with open(rst, 'w') as f:
        f.write(content)
"""

(From yocto-docs rev: ba49d9babfcb84bc5c26a68c8c3880a1d9c236d3)

Signed-off-by: Quentin Schulz <foss@0leil.net>
Reviewed-by: Michael Opdenacker <michael.opdenacker@bootlin.com>
Reviewed-by: Nicolas Dechesne <nicolas.dechesne@linaro.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/migration-guides/migration-1.7.rst

@@ -140,9 +140,9 @@ part of the variable name. This change not only simplifies usage but
 also allows the values of these variables to be appropriately
 incorporated into task signatures and thus trigger the appropriate tasks
 to re-execute when changed. You should replace any references to
-``module_autoload_*`` with ``KERNEL_MODULE_AUTOLOAD``, and add any
+``module_autoload_*`` with :term:`KERNEL_MODULE_AUTOLOAD`, and add any
 modules for which ``module_conf_*`` is specified to
-``KERNEL_MODULE_PROBECONF``.
+:term:`KERNEL_MODULE_PROBECONF`.
 
 .. _migration-1.7-qa-check-changes: