spi: mt7621: Disable clock in probe error path

spi: mt7621: Disable clock in probe error path

Commit 702b15cb9712 ("spi: mt7621: fix missing clk_disable_unprepare()
on error in mt7621_spi_probe") sought to disable the SYS clock on probe
errors, but only did so for 2 of 3 potentially failing calls:  The clock
needs to be disabled on failure of devm_spi_register_controller() as
well.

Moreover, the commit purports to fix a bug in commit cbd66c626e16 ("spi:
mt7621: Move SPI driver out of staging") but in reality the bug has
existed since the driver was first introduced.

Fixes: 1ab7f2a43558 ("staging: mt7621-spi: add mt7621 support")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v4.17+: 702b15cb9712: spi: mt7621: fix missing clk_disable_unprepare() on error in mt7621_spi_probe
Cc: <stable@vger.kernel.org> # v4.17+
Cc: Qinglang Miao <miaoqinglang@huawei.com>
Link: https://lore.kernel.org/r/36ad42760087952fb7c10aae7d2628547c26a7ec.1607286887.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>