ggml : ggml_compute_forward_concat() for arbitrary tensor type (ggml/1118)

* ggml_compute_forward_concat() for arbitrary tensor type

* Check that tensors' type match

* ggml-cpu.c: check type of source tensors

* ggml-cpu.c: move tensor type check to ggml_compute_forward_concat()

* ggml.c: check concatenated tensor type

* Remove tensor type check from ggml_compute_forward_concat() in ggml-cpu.c

..., as it was moved to ggml.c.

ggml/src/ggml.c

@@ -2332,6 +2332,7 @@ struct ggml_tensor * ggml_concat(
     struct ggml_tensor  * b,
     int                   dim) {
     GGML_ASSERT(dim >= 0 && dim < GGML_MAX_DIMS);
+    GGML_ASSERT(a->type == b->type);
 
     int64_t ne[GGML_MAX_DIMS];
     for (int d = 0; d < GGML_MAX_DIMS; ++d) {