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/cmd/usb_mass_storage.c b/cmd/usb_mass_storage.c
index b603730..a117ab2 100644
--- a/cmd/usb_mass_storage.c
+++ b/cmd/usb_mass_storage.c
@@ -135,8 +135,8 @@
 	return ret;
 }
 
-static int do_usb_mass_storage(cmd_tbl_t *cmdtp, int flag,
-			       int argc, char * const argv[])
+static int do_usb_mass_storage(struct cmd_tbl *cmdtp, int flag,
+			       int argc, char *const argv[])
 {
 	const char *usb_controller;
 	const char *devtype;