fs/erofs: add erofs filesystem support

This patch mainly deals with uncompressed files.

Signed-off-by: Huang Jianan <jnhuang95@gmail.com>
diff --git a/fs/Kconfig b/fs/Kconfig
index 620af7f..cda9f66 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -24,4 +24,6 @@
 
 source "fs/squashfs/Kconfig"
 
+source "fs/erofs/Kconfig"
+
 endmenu