powerpc: P5020: Remove macro CONFIG_PPC_P5020

Replace CONFIG_PPC_P5020 with ARCH_P5020 in Kconfig and clean up
existing macros.

Signed-off-by: York Sun <york.sun@nxp.com>
diff --git a/include/configs/cyrus.h b/include/configs/cyrus.h
index 4a11092..5f5138a 100644
--- a/include/configs/cyrus.h
+++ b/include/configs/cyrus.h
@@ -9,7 +9,7 @@
 
 #define CONFIG_CYRUS
 
-#if !defined(CONFIG_PPC_P5020) && !defined(CONFIG_PPC_P5040)
+#if !defined(CONFIG_ARCH_P5020) && !defined(CONFIG_PPC_P5040)
 #error Must call Cyrus CONFIG with a specific CPU enabled.
 #endif
 
@@ -18,7 +18,7 @@
 #define CONFIG_FSL_SATA_V2
 #define CONFIG_PCIE3
 #define CONFIG_PCIE4
-#ifdef CONFIG_PPC_P5020
+#ifdef CONFIG_ARCH_P5020
 #define CONFIG_SYS_FSL_RAID_ENGINE
 #define CONFIG_SYS_DPAA_RMAN
 #endif
@@ -30,7 +30,7 @@
 #define CONFIG_RAMBOOT_TEXT_BASE	CONFIG_SYS_TEXT_BASE
 #define CONFIG_RESET_VECTOR_ADDRESS	0xfffffffc
 #define CONFIG_SYS_FSL_PBL_PBI board/varisys/cyrus/pbi.cfg
-#if defined(CONFIG_PPC_P5020)
+#if defined(CONFIG_ARCH_P5020)
 #define CONFIG_SYS_CLK_FREQ 133000000
 #define CONFIG_SYS_FSL_PBL_RCW board/varisys/cyrus/rcw_p5020_v2.cfg
 #elif defined(CONFIG_PPC_P5040)