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/drivers/gpio/iproc_gpio.c b/drivers/gpio/iproc_gpio.c
index 8c143e9..7187d32 100644
--- a/drivers/gpio/iproc_gpio.c
+++ b/drivers/gpio/iproc_gpio.c
@@ -123,7 +123,7 @@
  * in private data structure to use it later while enabling gpio.
  *
  * @dev: pointer to GPIO device
- * @return 0 on success and -ENOMEM on failure
+ * Return: 0 on success and -ENOMEM on failure
  */
 static int iproc_get_gpio_pctrl_mapping(struct udevice *dev)
 {