sandbox: Force command sections to be 4-byte aligned

By default sections are 16-byte aligned on some architectures, but the
command name structure (struct cmd_tbl_s) does not have padding to
16 bytes. This reduces the alignment to 4-bytes so that the command
table can be accessed correctly on any architecture.

(Note: this needs doing properly)

Signed-off-by: Simon Glass <sjg@chromium.org>

include/command.h

@@ -117,7 +117,8 @@ extern int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]);
 #define CMD_FLAG_REPEAT		0x0001	/* repeat last command		*/
 #define CMD_FLAG_BOOTD		0x0002	/* command is from bootd	*/
 
-#define Struct_Section  __attribute__ ((unused,section (".u_boot_cmd")))
+#define Struct_Section  __attribute__((unused, section(".u_boot_cmd"), \
+		aligned(4)))
 
 #ifdef CONFIG_AUTO_COMPLETE
 # define _CMD_COMPLETE(x) x,