ggml-sycl : fix padding in timestep embedding kernel

This commit fixes the zero padding for odd dimensions in
the timestep embedding kernel.

Author: danbev

ggml/src/ggml-sycl/tsembd.cpp

@@ -21,11 +21,12 @@ static void timestep_embedding_f32(
     int j = item_ct1.get_local_id(2) + item_ct1.get_group(2) * item_ct1.get_local_range(2);
     float * embed_data = (float *)((char *)dst +  i*nb1);
 
-    if (dim % 2 != 0 && j == ((dim + 1) / 2)) {
-        embed_data[dim] = 0.f;
+    int half = dim / 2;
+
+    if (dim % 2 != 0 && j == half) {
+        embed_data[2 * half] = 0.f;
     }
 
-    int half = dim / 2;
     if (j >= half) {
         return;
     }