iop-adma: use iop_paranoia() for debug BUG_ONs

Now that the critical read back to flush the next descriptor address is
fixed we can downgrade some BUG_ONs that need only be enabled when testing
changes to the driver.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/arch/arm/mach-iop13xx/include/mach/adma.h b/arch/arm/mach-iop13xx/include/mach/adma.h
index 60019c8..5722e86 100644
--- a/arch/arm/mach-iop13xx/include/mach/adma.h
+++ b/arch/arm/mach-iop13xx/include/mach/adma.h
@@ -404,7 +404,8 @@
 					u32 next_desc_addr)
 {
 	struct iop13xx_adma_desc_hw *hw_desc = desc->hw_desc;
-	BUG_ON(hw_desc->next_desc);
+
+	iop_paranoia(hw_desc->next_desc);
 	hw_desc->next_desc = next_desc_addr;
 }