hammerhead: move CONFIG_SYS_TEXT_BASE to header

Signed-off-by: Andreas Bießmann <biessmann@corscience.de>

board/miromico/hammerhead/config.mk

@@ -1 +0,0 @@
-CONFIG_SYS_TEXT_BASE		= 0x00000000

include/configs/hammerhead.h

@@ -141,6 +141,7 @@
 #define CONFIG_SYS_MAX_FLASH_SECT		135
 
 #define CONFIG_SYS_MONITOR_BASE		CONFIG_SYS_FLASH_BASE
+#define CONFIG_SYS_TEXT_BASE		0x00000000
 
 #define CONFIG_SYS_INTRAM_BASE			0x24000000
 #define CONFIG_SYS_INTRAM_SIZE			0x8000