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>

cmd/setexpr.c

@@ -140,7 +140,7 @@ static char *memstr(const char *s1, int l1, const char *s2, int l2)
  * @olen: Length of @old excluding terminator
  * @new: New string to replace @old with
  * @nlen: Length of @new excluding terminator
- * @return pointer to immediately after the copied @new in @string, or NULL if
+ * Return: pointer to immediately after the copied @new in @string, or NULL if
  *	no replacement took place
  */
 static char *substitute(char *string, int *slen, int ssize,