drivers/power/pmic/pm8916.c: Make usid be uint32_t

If get_dev_addr fails it will return FDT_ADDR_T_NONE and:
>>>     "priv->usid == 4294967295U" is always false regardless of the values of its operands. This occurs as the logical operand of if.

Cc: Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
Reported-by: Coverity (CID: 143914)
Signed-off-by: Tom Rini <trini@konsulko.com>

drivers/power/pmic/pm8916.c

@@ -18,7 +18,7 @@ DECLARE_GLOBAL_DATA_PTR;
 #define REG_MASK 0xFF
 
 struct pm8916_priv {
-	uint16_t usid; /* Slave ID on SPMI bus */
+	uint32_t usid; /* Slave ID on SPMI bus */
 };
 
 static int pm8916_reg_count(struct udevice *dev)