taint: add explicit flag to show whether lock dep is still OK.

Fix up all callers as they were before, with make one change: an
unsigned module taints the kernel, but doesn't turn off lockdep.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c
index cbc624a..f32ab22 100644
--- a/arch/m68k/kernel/traps.c
+++ b/arch/m68k/kernel/traps.c
@@ -1176,7 +1176,7 @@
 	console_verbose();
 	printk("%s: %08x\n",str,nr);
 	show_registers(fp);
-	add_taint(TAINT_DIE);
+	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
 	do_exit(SIGSEGV);
 }