i2c: synquacer: fix deferred probing

The driver overrides the error codes returned by platform_get_irq() to
-ENODEV, so if it returns -EPROBE_DEFER, the driver will fail the probe
permanently instead of the deferred probing. Switch to propagating the
error codes upstream.

Fixes: 0d676a6c ("i2c: add support for Socionext SynQuacer I2C controller")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>