bitbake: data_smart: Don't cache/process capitalised overrides

Bitbake now only processes overrides which are lowercase since
this allows variables like SRC_URI not to pollute the cache.

There was a corner case where XXX_append_SomeThing was still being
processed (yet XXX_append_SomeThing_SomeOtherThing would not be).

This patch ensures we're consistent and only process lowercase
_append/_prepend and _remove operators too.

(Bitbake rev: 6eb56624e6d8dc1944e559b4f6584bfe66f566ba)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/data_smart.py

@@ -39,7 +39,7 @@ from bb.COW  import COWDictBase
 logger = logging.getLogger("BitBake.Data")
 
 __setvar_keyword__ = ["_append", "_prepend", "_remove"]
-__setvar_regexp__ = re.compile('(?P<base>.*?)(?P<keyword>_append|_prepend|_remove)(_(?P<add>.*))?$')
+__setvar_regexp__ = re.compile('(?P<base>.*?)(?P<keyword>_append|_prepend|_remove)(_(?P<add>[^A-Z]*))?$')
 __expand_var_regexp__ = re.compile(r"\${[^{}@\n\t :]+}")
 __expand_python_regexp__ = re.compile(r"\${@.+?}")