Merge pull request #853 from os-fpga/latest_vpr_add_pthread_flag

latest_vpr: add pthread flag to fix CentOS7 linking

Author: serge-dsa

include/CMAKE_fix/PATCHED_vpr_latest/CMakeLists.txt

@@ -116,8 +116,9 @@ if(NOT MSVC)
     set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -O0 -g3")
 endif()
 
-set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fPIC -O3 -mavx2")
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC -O3 -mavx2")
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fPIC -O3 -mavx2 -pthread")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC -O3 -mavx2 -pthread")
+set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -fPIC -O3 -mavx2 -pthread")
 
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