Merge pull request #1080 from junghans/as-needed-fix

cmake: fix link issue with --as-needed

cmake/CMakeLists.txt

@@ -276,11 +276,14 @@ endif()
 
 if(PKG_MSCG OR PKG_USER-ATC OR PKG_USER-AWPMD OR PKG_USER-QUIP OR PKG_LATTE)
   find_package(LAPACK)
-  if(NOT LAPACK_FOUND)
+  find_package(BLAS)
+  if(NOT LAPACK_FOUND OR NOT BLAS_FOUND)
     enable_language(Fortran)
     file(GLOB LAPACK_SOURCES ${LAMMPS_LIB_SOURCE_DIR}/linalg/*.[fF])
     add_library(linalg STATIC ${LAPACK_SOURCES})
     set(LAPACK_LIBRARIES linalg)
+  else()
+    list(APPEND LAPACK_LIBRARIES ${BLAS_LIBRARIES})
   endif()
 endif()