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/arch/nios2/lib/bootm.c b/arch/nios2/lib/bootm.c
index bec18fe..fed4129 100644
--- a/arch/nios2/lib/bootm.c
+++ b/arch/nios2/lib/bootm.c
@@ -6,12 +6,14 @@
 
 #include <common.h>
 #include <cpu_func.h>
+#include <env.h>
 #include <image.h>
 #include <irq_func.h>
 
 #define NIOS_MAGIC 0x534f494e /* enable command line and initrd passing */
 
-int do_bootm_linux(int flag, int argc, char * const argv[], bootm_headers_t *images)
+int do_bootm_linux(int flag, int argc, char *const argv[],
+		   bootm_headers_t *images)
 {
 	void (*kernel)(int, int, int, char *) = (void *)images->ep;
 	char *commandline = env_get("bootargs");