pnr/openroad: add missing mpl2 guard

Author: proppy

pnr/openroad/disable-mpl2.patch

@@ -1,5 +1,5 @@
 diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
-index 3383cc173..81777c996 100755
+index 3383cc173..79e66cecb 100755
 --- a/src/CMakeLists.txt
 +++ b/src/CMakeLists.txt
 @@ -168,6 +168,8 @@ message(STATUS "boost: ${Boost_VERSION}")
@@ -11,7 +11,18 @@ index 3383cc173..81777c996 100755
  option(ALLOW_WARNINGS "Flag to allow compilation with compiler warnings: on by default" ON)
  if (NOT ALLOW_WARNINGS)
    add_compile_options(
-@@ -325,12 +327,12 @@ target_link_libraries(openroad
+@@ -250,7 +252,9 @@ add_subdirectory(cts)
+ add_subdirectory(grt)
+ add_subdirectory(tap)
+ add_subdirectory(mpl)
+-add_subdirectory(mpl2)
++if ((NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin") AND BUILD_MPL2)
++  add_subdirectory(mpl2)
++endif()
+ add_subdirectory(rcx)
+ add_subdirectory(psm)
+ add_subdirectory(par)
+@@ -325,12 +329,12 @@ target_link_libraries(openroad
    ${CMAKE_THREAD_LIBS_INIT}
  )