[new uImage] Add new uImage format support to autoscript routine

autoscript() routine is updated to accept second argument, which
is only used for FIT images and provides a FIT subimage unit name.

autoscript() routine callers must now pass two arguments. For
non-interactive use (like in cmd_load.c, cmd_net.c), new environment
variable 'autoscript_uname' is introduced and used as a FIT
subimage unit name source.

autoscript command accepts extended syntax of the addr argument:
addr:<subimg_uname>

Signed-off-by: Marian Balakowicz <m8@semihalf.com>

board/pn62/cmd_pn62.c

@@ -157,8 +157,15 @@ int do_loadpci (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 	char *s;
 
 	if (((s = getenv("autoscript")) != NULL) && (strcmp(s,"yes") == 0)) {
-	    printf("Running autoscript at addr 0x%08lX ...\n", load_addr);
-	    rcode = autoscript (bd, load_addr);
+		printf ("Running autoscript at addr 0x%08lX", load_addr);
+
+		s = getenv ("autoscript_uname");
+		if (s)
+			printf (":%s ...\n", s);
+		else
+			puts (" ...\n");
+
+		rcode = autoscript (load_addr, s);
 	}
     }
 #endif