ethtool: Fix uninitialized variable use at qsfp dump

Struct sff_diags can be used uninitialized at sff8636_show_dom, this
caused the tool to show unreported fields (supports_alarms) by the lower
level driver.

In addition, make sure the same struct is being initialized at
sff8472_parse_eeprom function, to avoid the same issue here.

Fixes: a5e73bb ("ethtool:QSFP Plus/QSFP28 Diagnostics Information Support")
Signed-off-by: Eran Ben Elisha <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Signed-off-by: John W. Linville <[email protected]>

Author: Eran Ben Elisha

qsfp.c

@@ -671,7 +671,7 @@ static void sff8636_dom_parse(const __u8 *id, struct sff_diags *sd)
 
 static void sff8636_show_dom(const __u8 *id, __u32 eeprom_len)
 {
-	struct sff_diags sd;
+	struct sff_diags sd = {0};
 	char *rx_power_string = NULL;
 	char power_string[MAX_DESC_SIZE];
 	int i;

sfpdiag.c

@@ -241,7 +241,7 @@ static void sff8472_parse_eeprom(const __u8 *id, struct sff_diags *sd)
 
 void sff8472_show_all(const __u8 *id)
 {
-	struct sff_diags sd;
+	struct sff_diags sd = {0};
 	char *rx_power_string = NULL;
 	int i;