ddr: fsl: Merge macro CONFIG_NUM_DDR_CONTROLLERS and CONFIG_SYS_NUM_DDR_CTRLS

These two macros are used for the same thing, the total number of DDR
controllers for a given SoC. Use SYS_NUM_DDR_CTRLS in Kconfig and
merge existing usage.

Signed-off-by: York Sun <york.sun@nxp.com>
diff --git a/include/configs/T208xRDB.h b/include/configs/T208xRDB.h
index 325080f..1941188 100644
--- a/include/configs/T208xRDB.h
+++ b/include/configs/T208xRDB.h
@@ -26,7 +26,7 @@
 #endif
 
 #define CONFIG_SYS_FSL_CPC	/* Corenet Platform Cache */
-#define CONFIG_SYS_NUM_CPC	CONFIG_NUM_DDR_CONTROLLERS
+#define CONFIG_SYS_NUM_CPC	CONFIG_SYS_NUM_DDR_CTLRS
 #define CONFIG_FSL_IFC		/* Enable IFC Support */
 #define CONFIG_FSL_CAAM		/* Enable SEC/CAAM */
 #define CONFIG_ENV_OVERWRITE