fs/erofs: add filesystem commands

Add 'ls' and 'load' commands.

Signed-off-by: Huang Jianan <jnhuang95@gmail.com>
diff --git a/cmd/Kconfig b/cmd/Kconfig
index 1ed63fa..9d0e803 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -2201,6 +2201,12 @@
 	     cramfsls   - lists files in a cramfs image
 	     cramfsload - loads a file from a cramfs image
 
+config CMD_EROFS
+	bool "EROFS command support"
+	select FS_EROFS
+	help
+	  Support for the EROFS fs
+
 config CMD_EXT2
 	bool "ext2 command support"
 	select FS_EXT4