hidl-gen: remove references to AIDL

git grep -l _aidl_ . | xargs sed -i -e 's/_aidl_/_hidl_/g'

b/30778629 Generated code has many references to AIDL

Change-Id: I3172e7da7acd6ba8c8c332be7316317b0eb59136
Signed-off-by: Iliyan Malchev <malchev@google.com>
diff --git a/ScalarType.cpp b/ScalarType.cpp
index f308a72..b15734b 100644
--- a/ScalarType.cpp
+++ b/ScalarType.cpp
@@ -83,7 +83,7 @@
     const std::string parcelObjDeref =
         parcelObj + (parcelObjIsPointer ? "->" : ".");
 
-    out << "_aidl_err = "
+    out << "_hidl_err = "
         << parcelObjDeref
         << (isReader ? "read" : "write")
         << kSuffix[mKind]