Is your Julia 32bit or 64bit? It appears libcublas.so is 64bit, so either you need to install the 64bit version of Julia, or the 32bit version of libcublas.so.
I think you can determine which version of Julia you have by running versioninfo(). If the WORD_SIZE is 64 then you are 64bit, if it’s 32 then 32bit.