treewide: Convert CONFIG_HOSTNAME to a string option

CONFIG_HOSTNAME is defined as a "plain" preprocessor string, but every
use is couched by __stringify(...).

Hence, convert it to a proper string option.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/include/configs/woodburn_common.h b/include/configs/woodburn_common.h
index c11f17c..7e993b8 100644
--- a/include/configs/woodburn_common.h
+++ b/include/configs/woodburn_common.h
@@ -164,7 +164,7 @@
  * to update uboot and load kernel
  */
 
-#define CONFIG_HOSTNAME woodburn
+#define CONFIG_HOSTNAME "woodburn"
 #define	CONFIG_EXTRA_ENV_SETTINGS					\
 	"netdev=eth0\0"							\
 	"nfsargs=setenv bootargs root=/dev/nfs rw "			\
@@ -182,9 +182,9 @@
 	"addmisc=setenv bootargs ${bootargs} ${misc}\0"			\
 	"loadaddr=80800000\0"						\
 	"kernel_addr_r=80800000\0"					\
-	"hostname=" __stringify(CONFIG_HOSTNAME) "\0"			\
-	"bootfile=" __stringify(CONFIG_HOSTNAME) "/uImage\0"		\
-	"ramdisk_file=" __stringify(CONFIG_HOSTNAME) "/uRamdisk\0"	\
+	"hostname=" CONFIG_HOSTNAME "\0"			\
+	"bootfile=" CONFIG_HOSTNAME "/uImage\0"		\
+	"ramdisk_file=" CONFIG_HOSTNAME "/uRamdisk\0"	\
 	"flash_self=run ramargs addip addtty addmtd addmisc;"		\
 		"bootm ${kernel_addr} ${ramdisk_addr}\0"		\
 	"flash_nfs=run nfsargs addip addtty addmtd addmisc;"		\
@@ -198,7 +198,7 @@
 		"run ramargs addip addtty addmtd addmisc;"		\
 		"bootm ${kernel_addr_r} ${ramdisk_addr_r};"		\
 		"else echo Images not loades;fi\0"			\
-	"u-boot=" __stringify(CONFIG_HOSTNAME) "/u-boot.bin\0"		\
+	"u-boot=" CONFIG_HOSTNAME "/u-boot.bin\0"		\
 	"load=tftp ${loadaddr} ${u-boot}\0"				\
 	"uboot_addr=" __stringify(CONFIG_SYS_MONITOR_BASE) "\0"		\
 	"update=protect off ${uboot_addr} +80000;"			\