doc: replace @return by Return:

Sphinx expects Return: and not @return to indicate a return value.

find . -name '*.c' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

find . -name '*.h' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/arch/sandbox/cpu/state.c b/arch/sandbox/cpu/state.c
index 4e82253..ce904b1 100644
--- a/arch/sandbox/cpu/state.c
+++ b/arch/sandbox/cpu/state.c
@@ -101,7 +101,7 @@
  * @state: Sandbox state
  * @io: Method to use for reading state
  * @blob: FDT containing state
- * @return 0 if OK, -EINVAL if the read function returned failure
+ * Return: 0 if OK, -EINVAL if the read function returned failure
  */
 int sandbox_read_state_nodes(struct sandbox_state *state,
 			     struct sandbox_state_io *io, const void *blob)
@@ -190,7 +190,7 @@
  *
  * @state: Sandbox state
  * @io: Method to use for writing state
- * @return 0 if OK, -EIO if there is a fatal error (such as out of space
+ * Return: 0 if OK, -EIO if there is a fatal error (such as out of space
  * for adding the data), -EINVAL if the write function failed.
  */
 int sandbox_write_state_node(struct sandbox_state *state,