ggml-hexagon: gelu optimization (#18151)

* feat: working gelu with src0 put on vtcm

* feat: gelu ping-pong for both in and out

* fix: fixu compile error

* break: distinguish dma ddr->vtcm and vtcm->ddr operation

* fix: fix dma queue size

* break: update dma api to either pop src or dst ptr

* fix: fix activation vtcm allocation issue for src1 when swapperd

* refactor: ping-pong gelu logic to avoid unnecessary if else

* dma: improved queue interface and prefetch handling

* gelu: fix N+2 block prefetch

---------

Co-authored-by: Max Krasnyansky <maxk@qti.qualcomm.com>

ggml/src/ggml-hexagon/htp/hvx-utils.h

@@ -980,8 +980,6 @@ static inline void hvx_fast_sigmoid_f32(const uint8_t * restrict src, uint8_t *
     int step_of_1 = num_elems >> 5;
     int remaining = num_elems - step_of_1 * VLEN_FP32;
 
-    assert(remaining == 0);
-
     const HVX_Vector * restrict v_src = (HVX_Vector *) src;
     HVX_Vector * restrict v_dst       = (HVX_Vector *) dst;
 
@@ -996,8 +994,16 @@ static inline void hvx_fast_sigmoid_f32(const uint8_t * restrict src, uint8_t *
     for (int i = 0; i < step_of_1; i++) {
         v_dst[i] = hvx_vec_fast_sigmoid_fp32_guard(v_src[i], one, max_exp, min_exp);
     }
-}
 
+    if (remaining > 0) {
+        const float * srcf = ((const float *) src) + step_of_1* VLEN_FP32;
+        float *       dstf = (float *) dst + step_of_1*VLEN_FP32;
+
+        HVX_Vector in  = *(HVX_UVector *) srcf;
+        HVX_Vector out = hvx_vec_fast_sigmoid_fp32_guard(in, one, max_exp, min_exp);
+        hvx_vec_store_u((void *) dstf, remaining * SIZEOF_FP32, out);
+    }
+}
 
 static inline void hvx_sigmoid_f32(const uint8_t * restrict src, uint8_t * restrict dst, const int num_elems){
     int step_of_1 = num_elems >> 5;  // divby 32, because 32 float = 128 bytes per HVX vector