Fixed Linux linking for Armadillo

Signed-off-by: Thien Nguyen <nguyentm@ornl.gov>

quantum/plugins/algorithms/qite/CMakeLists.txt

@@ -49,6 +49,13 @@ else()
   set_target_properties(${LIBRARY_NAME}
                         PROPERTIES INSTALL_RPATH "$ORIGIN/../lib")
   set_target_properties(${LIBRARY_NAME} PROPERTIES LINK_FLAGS "-shared")
+  # Armadillo solver needs LAPACK
+  find_package(LAPACK)
+  if(LAPACK_FOUND)
+   target_link_libraries(${LIBRARY_NAME} PRIVATE ${LAPACK_LIBRARIES})
+  else()
+    message(STATUS "LAPACK NOT FOUND. QITE plugin may not work.")
+  endif()
 endif()
 
 if(XACC_BUILD_TESTS)