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/mac.c b/cmd/mac.c
index 4227d10..a39e116 100644
--- a/cmd/mac.c
+++ b/cmd/mac.c
@@ -7,7 +7,8 @@
 #include <common.h>
 #include <command.h>
 
-extern int do_mac(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]);
+extern int do_mac(struct cmd_tbl *cmdtp, int flag, int argc,
+		  char *const argv[]);
 
 U_BOOT_CMD(
 	mac, 3, 1,  do_mac,