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/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 3ff2678..535e888 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -661,7 +661,7 @@
 	pr_warn(PREFIX
 		"Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
 		table->signature, table->oem_table_id);
-	add_taint(TAINT_OVERRIDDEN_ACPI_TABLE);
+	add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
 }