*: kill bb_get_last_path_component, replace with two functions

(one which strips trailing slash and one which does not)
wget: straighten out as a result of above change
   text    data     bss     dec     hex filename
   5056       1       0    5057    13c1 busybox.t4/networking/wget.o
   5022       0       0    5022    139e busybox.t5/networking/wget.o

applets/applets.c

@@ -601,7 +601,7 @@ static int busybox_main(char **argv)
 	}
 	/* We support "busybox /a/path/to/applet args..." too. Allows for
 	 * "#!/bin/busybox"-style wrappers */
-	applet_name = bb_get_last_path_component(argv[0]);
+	applet_name = bb_get_last_path_component_nostrip(argv[0]);
 	run_applet_and_exit(applet_name, argv);
 	bb_error_msg_and_die("applet not found");
 }