Update the Target Description web page

- Update the Rust target document parts.

Signed-off-by: Chanhee Lee <[email protected]>

docs/reference/target-declaration.mdx

@@ -477,10 +477,10 @@ The `logging` option is one of `ERROR`, `WARN`, `INFO`, `LOG` or `DEBUG`. It spe
 ## no-compile
 
 <ShowIfs>
-<ShowIf ts rs >
+<ShowIf ts>
 This target does not support the `no-compile` target option.
 </ShowIf>
-<ShowIf c cpp py>
+<ShowIf c cpp py rs>
 If true, then do not invoke a target language compiler nor cmake. Just generate code.
 </ShowIf>
 </ShowIfs>
@@ -556,7 +556,8 @@ This specifies the scheduler to use. See[Target Language Details](<../reference/
 This target does not support the `single-file-project` target option.
 </ShowIf>
 <ShowIf rs>
-If true, enables [single-file project layout](#single-file-layout).
+{If true, enables [single-file project layout](#single-file-layout).}
+If true, only main.rs is generated instead of multiple rust source files.
 </ShowIf>
 </ShowIfs>