spi: sh-msiof: Add runtime PM lock in initializing

SH-MSIOF driver is enabled autosuspend API of spi framework.
But autosuspend framework doesn't work during initializing.
So runtime PM lock is added in SH-MSIOF driver initializing.

Fixes: e2a0ba54 (spi: sh-msiof: Convert to spi core auto_runtime_pm framework)
Signed-off-by: Hisashi Nakamura <hisashi.nakamura.ak@renesas.com>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org