[Libomptarget][remote] Add OpenMP linker flag to the plugin

The remote offloading server and plugin rely on OpenMP, so this needs to be added as a linker flag. Without this, applications segfault.

Differential Revision: https://reviews.llvm.org/D124200

Author: atmnpatel

openmp/libomptarget/plugins/remote/server/CMakeLists.txt

@@ -28,4 +28,5 @@ target_link_libraries(openmp-offloading-server
         protobuf
         absl::synchronization
         ${OPENMP_PTHREAD_LIB}
+        omp
         "-Wl,--version-script=${CMAKE_CURRENT_SOURCE_DIR}/../../exports")

openmp/libomptarget/plugins/remote/src/CMakeLists.txt

@@ -36,6 +36,7 @@ target_link_libraries(omptarget.rtl.rpc
   protobuf
   absl::synchronization
   ${OPENMP_PTHREAD_LIB}
+  omp
   "-Wl,--version-script=${CMAKE_CURRENT_SOURCE_DIR}/../../exports")
 
 # Report to the parent scope that we are building a plugin for RPC.