Expose per arch headers.

Bug: 73013352

Test: Compiles.
Change-Id: Ic05660db7d7858a9857143ee5e58cdaddcf52a35
diff --git a/libunwindstack/tests/ElfInterfaceArmTest.cpp b/libunwindstack/tests/ElfInterfaceArmTest.cpp
index 31d6a63..70a52ad 100644
--- a/libunwindstack/tests/ElfInterfaceArmTest.cpp
+++ b/libunwindstack/tests/ElfInterfaceArmTest.cpp
@@ -20,10 +20,10 @@
 
 #include <vector>
 
+#include <unwindstack/MachineArm.h>
 #include <unwindstack/RegsArm.h>
 
 #include "ElfInterfaceArm.h"
-#include "MachineArm.h"
 
 #include "ElfFake.h"
 #include "MemoryFake.h"