regulator: fix memory leak with repeated set_machine_constraints()

commit 57a6ad48 upstream.

Fixed commit introduced a possible second call to
set_machine_constraints() and that allocates memory for
rdev->constraints. Move the allocation to the caller so
it's easier to manage and done once.

Fixes: aea6cb99 ("regulator: resolve supply after creating regulator")
Cc: stable@vger.kernel.org
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # stpmic1
Link: https://lore.kernel.org/r/78c3d4016cebc08d441aad18cb924b4e4d9cf9df.1605226675.git.mirq-linux@rere.qmqm.pl


Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>