Stubbed HardwareRegister class

Commented out all of the ported PRD code in order to get the those .cpp
files to compile. Will eventually add code back in as we port the PRD
code to libhei.

Signed-off-by: Zane Shelley <zshelle@us.ibm.com>
Change-Id: If57f8a318cf82fb444cbef4867c1c34b06920496
diff --git a/test/simulator/meson.build b/test/simulator/meson.build
index 87b675b..b53dce5 100644
--- a/test/simulator/meson.build
+++ b/test/simulator/meson.build
@@ -1,6 +1,7 @@
 sim_sources = [
     'hei_sim_main.cpp',
     '../../src/isolator/hei_isolator.cpp',
+    '../../src/register/hei_hardware_register.cpp',
     '../../src/util/hei_bit_string.cpp',
 ]