Make address_space_get_iotlb_entry() take a MemTxAttrs argument

As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to address_space_get_iotlb_entry().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-12-peter.maydell@linaro.org
diff --git a/exec.c b/exec.c
index d54a56f..57c64c6 100644
--- a/exec.c
+++ b/exec.c
@@ -582,7 +582,7 @@
 
 /* Called from RCU critical section */
 IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace *as, hwaddr addr,
-                                            bool is_write)
+                                            bool is_write, MemTxAttrs attrs)
 {
     MemoryRegionSection section;
     hwaddr xlat, page_mask;