Merge pull request #322 from 3405691582/OpenBSDSupport

OpenBSD support.

Author: briancroom

cmake/modules/SwiftSupport.cmake

@@ -22,6 +22,8 @@ function(get_swift_host_arch result_var_name)
     set("${result_var_name}" "armv7" PARENT_SCOPE)
   elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "armv7-a")
     set("${result_var_name}" "armv7" PARENT_SCOPE)
+  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "amd64")
+    set("${result_var_name}" "amd64" PARENT_SCOPE)
   elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "AMD64")
     set("${result_var_name}" "x86_64" PARENT_SCOPE)
   elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "IA64")