PPC MPC83xx: Fix MPC8323ERDB build warning

Fix:

mpc8323erdb.c: In function 'mac_read_from_eeprom':
mpc8323erdb.c:198:3: warning: dereferencing type-punned pointer will
break strict-aliasing rules [-Wstrict-aliasing]

Signed-off-by: Wolfgang Denk <wd@denx.de>
cc: Timur Tabi <timur@tabi.org>
cc: Kim Phillips <kim.phillips@freescale.com>

board/freescale/mpc8323erdb/mpc8323erdb.c

@@ -195,7 +195,11 @@ int mac_read_from_eeprom(void)
 		printf("\nEEPROM @ 0x%02x read FAILED!!!\n",
 		       CONFIG_SYS_I2C_EEPROM_ADDR);
 	} else {
-		if (crc32(crc, buf, 24) == *(unsigned int *)&buf[24]) {
+		uint32_t crc_buf;
+
+		memcpy(&crc_buf, &buf[24], sizeof(uint32_t));
+
+		if (crc32(crc, buf, 24) == crc_buf) {
 			printf("Reading MAC from EEPROM\n");
 			for (i = 0; i < 4; i++) {
 				if (memcmp(&buf[i * 6], "\0\0\0\0\0\0", 6)) {