ggml: fix ggml_is_contiguous_n for ne == 1 (#20092)

Author: JohannesGaessler

ggml/src/ggml.c

@@ -1410,16 +1410,14 @@ static bool ggml_is_contiguous_n(const struct ggml_tensor * tensor, int n) {
     }
     next_nb *= tensor->ne[0]/ggml_blck_size(tensor->type);
     for (int i = 1; i < GGML_MAX_DIMS; i++) {
-        if (tensor->ne[i] != 1) {
-            if (i > n) {
-                if (tensor->nb[i] != next_nb) {
-                    return false;
-                }
-                next_nb *= tensor->ne[i];
-            } else {
-                // this dimension does not need to be contiguous
-                next_nb = tensor->ne[i]*tensor->nb[i];
+        if (i > n) {
+            if (tensor->ne[i] != 1 && tensor->nb[i] != next_nb) {
+                return false;
             }
+            next_nb *= tensor->ne[i];
+        } else {
+            // this dimension does not need to be contiguous
+            next_nb = tensor->ne[i]*tensor->nb[i];
         }
     }
     return true;