Fixed some OpenCL interface bugs

modules/core/include/opencv2/core/ocl.hpp

@@ -584,7 +584,6 @@ public:
     Program();
     Program(const ProgramSource& src,
             const String& buildflags, String& errmsg);
-    explicit Program(const String& buf);
     Program(const Program& prog);
 
     Program& operator = (const Program& prog);

modules/core/src/ocl.cpp

@@ -2143,7 +2143,7 @@ int Kernel::set(int i, const Image2D& image2D)
 
 int Kernel::set(int i, const UMat& m)
 {
-    return set(i, KernelArg(KernelArg::READ_WRITE, (UMat*)&m, 0, 0));
+    return set(i, KernelArg(KernelArg::READ_WRITE, (UMat*)&m));
 }
 
 int Kernel::set(int i, const KernelArg& arg)