spi: synquacer: Disable clock in probe error path

If the calls to platform_get_irq() or devm_request_irq() fail on probe
of the SynQuacer SPI driver, the clock "sspi->clk" is erroneously not
unprepared and disabled.

If the clock rate "master->max_speed_hz" cannot be determined, the same
happens and in addition the spi_master struct is not freed.

Fix it.

Fixes: b0823ee3 ("spi: Add spi driver for Socionext SynQuacer platform")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v5.3+
Cc: Masahisa Kojima <masahisa.kojima@linaro.org>
Link: https://lore.kernel.org/r/232281df1ab91d8f0f553a62d5f97fc264ace4da.1604874488.git.lukas@wunner.de


Signed-off-by: Mark Brown <broonie@kernel.org>