drivers: gpio_adp5585: fix input register address

The input register address was somehow missing, fix it.

Signed-off-by: Chekhov Ma <chekhov.ma@nxp.com>
(cherry picked from commit 7726b70033be65207a479856c97af996bcf75c26)
diff --git a/drivers/gpio/gpio_adp5585.c b/drivers/gpio/gpio_adp5585.c
index 8b77764..0bb247c 100644
--- a/drivers/gpio/gpio_adp5585.c
+++ b/drivers/gpio/gpio_adp5585.c
@@ -193,7 +193,7 @@
 
 	/** Read Input Register */
 
-	uint8_t gpi_status_reg;
+	uint8_t gpi_status_reg = ADP5585_GPI_STATUS_A;
 	uint8_t gpi_status_buf[2];
 
 	ret = i2c_write_read_dt(&parent_cfg->i2c_bus, &gpi_status_reg, 1U,