deleted extra arg in case of power=0.5

modules/core/src/mathfuncs.cpp

@@ -2057,10 +2057,15 @@ static bool ocl_pow(InputArray _src, double power, OutputArray _dst)
     ocl::KernelArg srcarg = ocl::KernelArg::ReadOnlyNoSize(src),
             dstarg = ocl::KernelArg::WriteOnly(dst, cn);
 
+    if (issqrt)
+        k.args(srcarg, dstarg);
+    else
+    {
         if (depth == CV_32F)
             k.args(srcarg, dstarg, (float)power);
         else
             k.args(srcarg, dstarg, power);
+    }
 
     size_t globalsize[2] = { dst.cols *  cn, dst.rows };
     return k.run(2, globalsize, NULL, false);