fix compiler warning

Author: JohannesGaessler

ggml-cuda/fattn.cu

@@ -225,12 +225,11 @@ static __global__ void flash_attn_vec_ext_f16(
         dst[j_dst*D*gridDim.y + D*blockIdx.y + tid] = dst_val;
     }
 
-    if (parallel_blocks == 1 || tid != 0) {
-        return;
-    }
+    if (parallel_blocks != 1 && tid != 0) {
 #pragma unroll
-    for (int j = 0; j < ncols; ++j) {
-        dst_meta[(ic0 + j)*gridDim.y*parallel_blocks + blockIdx.y*parallel_blocks + ip] = make_float2(kqmax[j], kqsum[j]);
+        for (int j = 0; j < ncols; ++j) {
+            dst_meta[(ic0 + j)*gridDim.y*parallel_blocks + blockIdx.y*parallel_blocks + ip] = make_float2(kqmax[j], kqsum[j]);
+        }
     }
 #else
    NO_DEVICE_CODE;