exec.c: update tlb_reset_dirty_range_all().

Change-Id: I0ba2671c5bde01b0b3e1c29679c39b0a45ff7999
diff --git a/exec.c b/exec.c
index 0040ddc..47c8825 100644
--- a/exec.c
+++ b/exec.c
@@ -521,13 +521,16 @@
 
 static void tlb_reset_dirty_range_all(ram_addr_t start, ram_addr_t length)
 {
-    ram_addr_t end = TARGET_PAGE_ALIGN(start + length);
+    ram_addr_t start1;
+    RAMBlock *block;
+    ram_addr_t end;
 
+    end = TARGET_PAGE_ALIGN(start + length);
     start &= TARGET_PAGE_MASK;
 
-    RAMBlock* block = qemu_get_ram_block(start);
+    block = qemu_get_ram_block(start);
     assert(block == qemu_get_ram_block(end - 1));
-    uintptr_t start1 = (uintptr_t)block->host + (start - block->offset);
+    start1 = (uintptr_t)block->host + (start - block->offset);
     cpu_tlb_reset_dirty_all(start1, length);
 }