powerpc: B4860: Remove macro CONFIG_PPC_B4860

Replace CONFIG_PPC_B4860 with ARCH_B4860 in Kconfig and clean up
existing macros.

Signed-off-by: York Sun <york.sun@nxp.com>
diff --git a/arch/powerpc/cpu/mpc85xx/Kconfig b/arch/powerpc/cpu/mpc85xx/Kconfig
index 31a074e..962ec2b 100644
--- a/arch/powerpc/cpu/mpc85xx/Kconfig
+++ b/arch/powerpc/cpu/mpc85xx/Kconfig
@@ -23,6 +23,7 @@
 
 config TARGET_B4860QDS
 	bool "Support B4860QDS"
+	select ARCH_B4860
 	select SUPPORT_SPL
 	select PHYS_64BIT
 
@@ -256,6 +257,9 @@
 
 endchoice
 
+config ARCH_B4860
+	bool
+
 config ARCH_BSC9131
 	bool
 
diff --git a/arch/powerpc/cpu/mpc85xx/Makefile b/arch/powerpc/cpu/mpc85xx/Makefile
index 7c1dbb9..87d8b18 100644
--- a/arch/powerpc/cpu/mpc85xx/Makefile
+++ b/arch/powerpc/cpu/mpc85xx/Makefile
@@ -48,7 +48,7 @@
 obj-$(CONFIG_PPC_T4160) += t4240_ids.o
 obj-$(CONFIG_PPC_T4080) += t4240_ids.o
 obj-$(CONFIG_PPC_B4420) += b4860_ids.o
-obj-$(CONFIG_PPC_B4860) += b4860_ids.o
+obj-$(CONFIG_ARCH_B4860) += b4860_ids.o
 obj-$(CONFIG_PPC_T1040) += t1040_ids.o
 obj-$(CONFIG_PPC_T1042)	+= t1040_ids.o
 obj-$(CONFIG_PPC_T1020)	+= t1040_ids.o
@@ -90,7 +90,7 @@
 obj-$(CONFIG_PPC_T4160) += t4240_serdes.o
 obj-$(CONFIG_PPC_T4080) += t4240_serdes.o
 obj-$(CONFIG_PPC_B4420) += b4860_serdes.o
-obj-$(CONFIG_PPC_B4860) += b4860_serdes.o
+obj-$(CONFIG_ARCH_B4860) += b4860_serdes.o
 obj-$(CONFIG_ARCH_BSC9132) += bsc9132_serdes.o
 obj-$(CONFIG_PPC_T1040) += t1040_serdes.o
 obj-$(CONFIG_PPC_T1042)	+= t1040_serdes.o
diff --git a/arch/powerpc/cpu/mpc85xx/b4860_serdes.c b/arch/powerpc/cpu/mpc85xx/b4860_serdes.c
index 63172de..64db7a7 100644
--- a/arch/powerpc/cpu/mpc85xx/b4860_serdes.c
+++ b/arch/powerpc/cpu/mpc85xx/b4860_serdes.c
@@ -15,7 +15,7 @@
 	u8 lanes[SRDS_MAX_LANES];
 };
 
-#ifdef CONFIG_PPC_B4860
+#ifdef CONFIG_ARCH_B4860
 static struct serdes_config serdes1_cfg_tbl[] = {
 	/* SerDes 1 */
 	{0x01, {AURORA, AURORA, CPRI6, CPRI5,
diff --git a/arch/powerpc/cpu/mpc85xx/speed.c b/arch/powerpc/cpu/mpc85xx/speed.c
index 38a28a8..2d3517b 100644
--- a/arch/powerpc/cpu/mpc85xx/speed.c
+++ b/arch/powerpc/cpu/mpc85xx/speed.c
@@ -202,7 +202,7 @@
 	}
 #endif
 
-#if defined(CONFIG_PPC_B4860) || defined(CONFIG_PPC_B4420) || \
+#if defined(CONFIG_ARCH_B4860) || defined(CONFIG_PPC_B4420) || \
 	defined(CONFIG_PPC_T2080) || defined(CONFIG_PPC_T2081)
 #define FM1_CLK_SEL	0xe0000000
 #define FM1_CLK_SHIFT	29