powerpc: T1040D4RDB: Separate from T1040RDB in Kconfig

Use TARGET_T1040D4RDB in Kconfig to simplify config macros. Replace
CONFIG_T1040D4RDB with TARGET_T1040D4RDB and clean up existing macros.

Signed-off-by: York Sun <york.sun@nxp.com>
diff --git a/board/freescale/t104xrdb/Kconfig b/board/freescale/t104xrdb/Kconfig
index 5b6095b..2a633c0 100644
--- a/board/freescale/t104xrdb/Kconfig
+++ b/board/freescale/t104xrdb/Kconfig
@@ -1,4 +1,4 @@
-if TARGET_T1040RDB || TARGET_T1042RDB
+if TARGET_T1040RDB || TARGET_T1040D4RDB || TARGET_T1042RDB
 
 config SYS_BOARD
 	default "t104xrdb"
diff --git a/board/freescale/t104xrdb/eth.c b/board/freescale/t104xrdb/eth.c
index 52cd112..ea9f450 100644
--- a/board/freescale/t104xrdb/eth.c
+++ b/board/freescale/t104xrdb/eth.c
@@ -43,7 +43,7 @@
 		int idx = i - FM1_DTSEC1;
 
 		switch (fm_info_get_enet_if(i)) {
-#if defined(CONFIG_T1040RDB) || defined(CONFIG_T1040D4RDB)
+#if defined(CONFIG_T1040RDB) || defined(CONFIG_TARGET_T1040D4RDB)
 		case PHY_INTERFACE_MODE_SGMII:
 			/* T1040RDB & T1040D4RDB only supports SGMII on
 			 * DTSEC3
diff --git a/board/freescale/t104xrdb/t104xrdb.c b/board/freescale/t104xrdb/t104xrdb.c
index 6bad6a454..803666e 100644
--- a/board/freescale/t104xrdb/t104xrdb.c
+++ b/board/freescale/t104xrdb/t104xrdb.c
@@ -105,7 +105,7 @@
 		CPLD_WRITE(misc_ctl_status, CPLD_READ(misc_ctl_status) |
 					 MISC_CTL_SG_SEL | MISC_CTL_AURORA_SEL);
 
-#if defined(CONFIG_T1040D4RDB)
+#if defined(CONFIG_TARGET_T1040D4RDB)
 	if (hwconfig("qe-tdm")) {
 		CPLD_WRITE(sfp_ctl_status, CPLD_READ(sfp_ctl_status) |
 			   MISC_MUX_QE_TDM);