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/disk/part_efi.c b/disk/part_efi.c
index 3809333..611654f 100644
--- a/disk/part_efi.c
+++ b/disk/part_efi.c
@@ -331,7 +331,7 @@
  * set_protective_mbr(): Set the EFI protective MBR
  * @param dev_desc - block device descriptor
  *
- * @return - zero on success, otherwise error
+ * Return: - zero on success, otherwise error
  */
 static int set_protective_mbr(struct blk_desc *dev_desc)
 {