lib: consolidate hang()

Delete all occurrences of hang() and provide a generic function.

Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
Acked-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
[trini: Modify check around puts() in hang.c slightly]
Signed-off-by: Tom Rini <trini@ti.com>

arch/microblaze/lib/board.c

@@ -195,10 +195,3 @@ void board_init_f(ulong not_used)
 		main_loop();
 	}
 }
-
-void hang(void)
-{
-	puts("### ERROR ### Please RESET the board ###\n");
-	for (;;)
-		;
-}