Input: synaptics-rmi4 - change a char type to u8

Smatch doesn't like when we use "%02X" to print char types because,
what about if it's a negative?

Signed-off-by: Dan Carpenter <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/rmi4/rmi_f34v7.c

···
 			query_1_7.partition_support[1] & HAS_GUEST_CODE;
 
 	if (query_0 & HAS_CONFIG_ID) {
-		char f34_ctrl[CONFIG_ID_SIZE];
+		u8 f34_ctrl[CONFIG_ID_SIZE];
 		int i = 0;
 		u8 *p = f34->configuration_id;
 		*p = '\0';