mainboard/hp/dl145_g3/get_bus_conf.c: Use ARRAY_SIZE macro

Change-Id: Ie3287cba45bd6f4f8823ce03cd9983707c9ad0de
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/6194
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
Tested-by: build bot (Jenkins)

src/mainboard/hp/dl145_g3/get_bus_conf.c

@@ -82,7 +82,7 @@ void get_bus_conf(void)
 
 	m = sysconf.mb;
 
-	sysconf.hc_possible_num = sizeof(pci1234x)/sizeof(pci1234x[0]);
+	sysconf.hc_possible_num = ARRAY_SIZE(pci1234x);
 
 	for(i=0;i<sysconf.hc_possible_num; i++) {
 		sysconf.pci1234[i] = pci1234x[i];