Fix Libdl deprecation

Author: isuruf

src/SymEngine.jl

@@ -3,7 +3,7 @@ __precompile__()
 module SymEngine
 
 import Base: show, convert, real, imag
-import Compat: String, unsafe_string, @compat, denominator, numerator, invokelatest, Cvoid, Nothing, MathConstants.γ, MathConstants.e, MathConstants.φ, MathConstants.catalan, LinearAlgebra, finalizer
+import Compat: String, unsafe_string, @compat, denominator, numerator, invokelatest, Cvoid, Nothing, MathConstants.γ, MathConstants.e, MathConstants.φ, MathConstants.catalan, LinearAlgebra, finalizer, Libdl
 
 export Basic, symbols, @vars, @funs, SymFunction
 export free_symbols, get_args

src/utils.jl

@@ -1,6 +1,6 @@
 "Helper function to lookup a symbol from libsymengine"
 function get_symbol(sym::Symbol)
-    handle = Base.Libdl.dlopen_e(libsymengine)
+    handle = Libdl.dlopen_e(libsymengine)
     if handle == C_NULL
         C_NULL
     else