flash: compile common/flash.c iif CONFIG_MTD_NO_FLASH is enabled

The whole of common/flash.c is guarded by #if defined() ... #endif.
Move the conditional to common/Makefile.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/common/Makefile b/common/Makefile
index ecc23e6..86225f1 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -67,7 +67,7 @@
 # others
 obj-$(CONFIG_BOOTSTAGE) += bootstage.o
 obj-$(CONFIG_CONSOLE_MUX) += iomux.o
-obj-y += flash.o
+obj-$(CONFIG_MTD_NOR_FLASH) += flash.o
 obj-$(CONFIG_CMD_KGDB) += kgdb.o kgdb_stubs.o
 obj-$(CONFIG_I2C_EDID) += edid.o
 obj-$(CONFIG_KALLSYMS) += kallsyms.o
diff --git a/common/flash.c b/common/flash.c
index 6d492c7..587ef60 100644
--- a/common/flash.c
+++ b/common/flash.c
@@ -10,7 +10,6 @@
 #include <common.h>
 #include <flash.h>
 
-#if defined(CONFIG_MTD_NOR_FLASH)
 #include <mtd/cfi_flash.h>
 
 extern flash_info_t  flash_info[]; /* info for FLASH chips */
@@ -218,7 +217,3 @@
 		break;
 	}
 }
-
-/*-----------------------------------------------------------------------
- */
-#endif /* !CONFIG_MTD_NOR_FLASH */