configs: stm32f4xx: Remove CONFIG_SYS_RAM_FREQ_DIV

Since commit bfea69ad2793 ("stm32f7: sdram: correct sdram
configuration as per micron sdram"), CONFIG_SYS_RAM_FREQ_DIV
flag is no more used, remove it.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
diff --git a/include/configs/stm32f429-discovery.h b/include/configs/stm32f429-discovery.h
index 90d7429..b8848f1 100644
--- a/include/configs/stm32f429-discovery.h
+++ b/include/configs/stm32f429-discovery.h
@@ -17,7 +17,6 @@
  * Configuration of the external SDRAM memory
  */
 #define CONFIG_NR_DRAM_BANKS		1
-#define CONFIG_SYS_RAM_FREQ_DIV		2
 #define CONFIG_SYS_LOAD_ADDR		0x90400000
 #define CONFIG_LOADADDR			0x90400000
 
diff --git a/include/configs/stm32f429-evaluation.h b/include/configs/stm32f429-evaluation.h
index d48940d..ab730e1 100644
--- a/include/configs/stm32f429-evaluation.h
+++ b/include/configs/stm32f429-evaluation.h
@@ -17,7 +17,6 @@
  * Configuration of the external SDRAM memory
  */
 #define CONFIG_NR_DRAM_BANKS		1
-#define CONFIG_SYS_RAM_FREQ_DIV		2
 #define CONFIG_SYS_LOAD_ADDR		0x00400000
 #define CONFIG_LOADADDR			0x00400000
 
diff --git a/include/configs/stm32f469-discovery.h b/include/configs/stm32f469-discovery.h
index be8c233..3e4e89b 100644
--- a/include/configs/stm32f469-discovery.h
+++ b/include/configs/stm32f469-discovery.h
@@ -17,7 +17,6 @@
  * Configuration of the external SDRAM memory
  */
 #define CONFIG_NR_DRAM_BANKS		1
-#define CONFIG_SYS_RAM_FREQ_DIV		2
 #define CONFIG_SYS_LOAD_ADDR		0x00400000
 #define CONFIG_LOADADDR			0x00400000