ggml : sync alibi fix from ggml repo

ggml.c

@@ -8553,7 +8553,7 @@ static void ggml_compute_forward_alibi_f32(
                     m_k = powf(m1, 2 * (k - n_heads_log2_floor) + 1);
                 }
 
-                pdst[0] = (j+1) * m_k + src[0];
+                pdst[0] = i * m_k + src[0];
             }
         }
     }
@@ -8615,7 +8615,7 @@ static void ggml_compute_forward_alibi_f16(
                 }
 
                 // we return F32
-                pdst[0] = (j+1) * m_k + GGML_FP16_TO_FP32(src[0]);
+                pdst[0] = i * m_k + GGML_FP16_TO_FP32(src[0]);
             }
         }
     }