nvme: Add show routine to print detailed information

This adds nvme_print_info() to show detailed NVMe controller and
namespace information.

Signed-off-by: Zhikang Zhang <zhikang.zhang@nxp.com>
Signed-off-by: Wenbin Song <wenbin.song@nxp.com>
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/include/nvme.h b/include/nvme.h
index 3624408..8375d61 100644
--- a/include/nvme.h
+++ b/include/nvme.h
@@ -68,4 +68,15 @@
  */
 int nvme_scan_namespace(void);
 
+/**
+ * nvme_print_info - print detailed NVMe controller and namespace information
+ *
+ * This prints out detailed human readable NVMe controller and namespace
+ * information which is very useful for debugging.
+ *
+ * @udev:	NVMe controller device
+ * @return:	0 on success, -EIO if NVMe identify command fails
+ */
+int nvme_print_info(struct udevice *udev);
+
 #endif /* __NVME_H__ */