Stamp out some x86/host mode warnings

Nuked a void* cast warnings and moved cacheflush into a target-specific
utility wrapper.

Change-Id: I36c841288b9ec7e03c0cb29b2e89db344f36fad1
diff --git a/vm/compiler/codegen/arm/ArchUtility.c b/vm/compiler/codegen/arm/ArchUtility.c
index 8682c1a..95b96c4 100644
--- a/vm/compiler/codegen/arm/ArchUtility.c
+++ b/vm/compiler/codegen/arm/ArchUtility.c
@@ -385,3 +385,9 @@
              armLIR->operands[0]);
     }
 }
+
+/* Target-specific cache flushing */
+int dvmCompilerCacheFlush(long start, long end, long flags)
+{
+    return cacheflush(start, end, flags);
+}