blk: Make functions available unconditionally

Some boards still don't enable BLK but we want to be able to at least
compile the code which relies on this. For example, bootstd includes
calls to blk_...() functions, albeit with a check for BLK so that the
code is eliminated by the compiler.

Reduce the scope of the BLK #ifdef to help with this.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/blk.h b/include/blk.h
index 1fc9a5b..eef6c86 100644
--- a/include/blk.h
+++ b/include/blk.h
@@ -197,7 +197,6 @@
 
 #endif
 
-#if CONFIG_IS_ENABLED(BLK)
 struct udevice;
 
 /* Operations on block devices */
@@ -278,6 +277,8 @@
 #endif	/* CONFIG_BOUNCE_BUFFER */
 };
 
+#if CONFIG_IS_ENABLED(BLK)
+
 /*
  * These functions should take struct udevice instead of struct blk_desc,
  * but this is convenient for migration to driver model. Add a 'd' prefix
@@ -291,6 +292,8 @@
 unsigned long blk_derase(struct blk_desc *block_dev, lbaint_t start,
 			 lbaint_t blkcnt);
 
+#endif /* BLK */
+
 /**
  * blk_read() - Read from a block device
  *
@@ -528,8 +531,10 @@
  */
 int blk_get_desc(enum uclass_id uclass_id, int devnum, struct blk_desc **descp);
 
-#else
+#if !CONFIG_IS_ENABLED(BLK)
+
 #include <errno.h>
+
 /*
  * These functions should take struct udevice instead of struct blk_desc,
  * but this is convenient for migration to driver model. Add a 'd' prefix