Use 64-bit BLAS more consistently when Base.USE_BLAS64 is set

Author: ViralBShah

stdlib/OpenBLAS_jll/src/OpenBLAS_jll.jl

@@ -17,7 +17,7 @@ artifact_dir = ""
 libopenblas_handle = C_NULL
 libopenblas_path = ""
 
-if Sys.WORD_SIZE == 64
+if Base.USE_BLAS64
     const libsuffix = "64_"
 else
     const libsuffix = ""