cmd: inconsistent return type of command_process()

The declarations in the header and in the implementation must match.

Reported-by: Sergei Antonov <saproj@gmail.com>
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

include/command.h

@@ -229,10 +229,10 @@ enum command_ret_t {
  *			is left unchanged.
  * @param ticks		If ticks is not null, this function set it to the
  *			number of ticks the command took to complete.
- * Return: 0 if the command succeeded, 1 if it failed
+ * Return: 0 if command succeeded, else non-zero (CMD_RET_...)
  */
-int cmd_process(int flag, int argc, char *const argv[], int *repeatable,
-		unsigned long *ticks);
+enum command_ret_t cmd_process(int flag, int argc, char *const argv[],
+			       int *repeatable, unsigned long *ticks);
 
 void fixup_cmdtable(struct cmd_tbl *cmdtp, int size);