blackfin: convert blackfin board_f and board_r to use generic board init functions

- move blackfin specific cpu init code from blackfin board.c to cpu.c
- remove blackfin specific board init code and invoke generic board_f fron cpu init entry
- rename section name bss_vma to bss_start in order to match the generic board init code
- add a fake relocate_code function to set up the new stack only

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
diff --git a/include/configs/bf506f-ezkit.h b/include/configs/bf506f-ezkit.h
index eed2d5b..5db1819 100644
--- a/include/configs/bf506f-ezkit.h
+++ b/include/configs/bf506f-ezkit.h
@@ -56,7 +56,7 @@
 /*
  * Flash Settings
  */
-
+/*
 #define CONFIG_FLASH_CFI_DRIVER
 #define CONFIG_SYS_FLASH_BASE		0x20000000
 #define CONFIG_SYS_FLASH_CFI
@@ -64,9 +64,8 @@
 #define CONFIG_SYS_MAX_FLASH_SECT	71
 #define CONFIG_CMD_FLASH
 #define CONFIG_MONITOR_IS_IN_RAM
-/*
-#define CONFIG_SYS_NO_FLASH
 */
+#define CONFIG_SYS_NO_FLASH
 
 /*
  * SPI Settings