This was writing out locked-sigs.inc into cwd with every
'bitbake -S' invocation. When the intent is only to to get task
stamps (-S none), or print the difference between them (-S printdiff),
the file is unnecessary clutter.
A couple of selftests/scripts were however relying on this, so they're
adjusted to explicitly request the file.
eSDK code calls dump_lockedsigs() separately via
oe.copy_buildsystem.generate_locked_sigs() and so isn't affected.
(From OE-Core rev: ad57c3cac2a8d3e60222e3cca0685f582dcea135)
Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>