chore(libcard10): Fix all sign-compare warnings

Signed-off-by: Rahix <rahix@rahix.de>

lib/card10/card10.c

@@ -69,7 +69,7 @@ void card10_init(void)
 	)
 		;
 	/* If we don't have a valid time yet, set it to 2019-01-01 */
-	if (RTC_GetSecond() < 1546300800UL) {
+	if (RTC_GetSecond() < 1546300800L) {
 		while (RTC_Init(MXC_RTC, 1546300800UL, 0, NULL) == E_BUSY)
 			;
 	}

lib/card10/portexpander.c

@@ -100,7 +100,7 @@ int portexpander_init(void)
 
 	// Enable pull-ups for buttons
 	// Enable outputs for the transistors, the LED and the LCD reset
-	for (int i = 0; i < sizeof(pe_pin_config) / sizeof(pe_pin_config[0]);
+	for (size_t i = 0; i < sizeof(pe_pin_config) / sizeof(pe_pin_config[0]);
 	     i++) {
 		ret = portexpander_config(&pe_pin_config[i]);
 		MXC_ASSERT(ret == E_NO_ERROR);