command: Remove the cmd_tbl_t typedef

We should not use typedefs in U-Boot. They cannot be used as forward
declarations which means that header files must include the full header to
access them.

Drop the typedef and rename the struct to remove the _s suffix which is
now not useful.

This requires quite a few header-file additions.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/board/freescale/common/vid.c b/board/freescale/common/vid.c
index 2085247..dfc6a91 100644
--- a/board/freescale/common/vid.c
+++ b/board/freescale/common/vid.c
@@ -925,9 +925,9 @@
 
 }
 
-static int do_vdd_override(cmd_tbl_t *cmdtp,
+static int do_vdd_override(struct cmd_tbl *cmdtp,
 			   int flag, int argc,
-			   char * const argv[])
+			   char *const argv[])
 {
 	ulong override;
 
@@ -941,9 +941,8 @@
 	return 0;
 }
 
-static int do_vdd_read(cmd_tbl_t *cmdtp,
-			 int flag, int argc,
-			 char * const argv[])
+static int do_vdd_read(struct cmd_tbl *cmdtp, int flag, int argc,
+		       char *const argv[])
 {
 	if (argc < 1)
 		return CMD_RET_USAGE;