Hexagon: DAIG op (#22195)

* hexagon: Add DIAG op

* hexagon: add HVX support and DMA double buffering

* hexagon: fix fatal error

* hexagon: remove as many pragma(s) as possible

ggml/src/ggml-hexagon/htp/main.c

@@ -514,6 +514,9 @@ static int execute_op(struct htp_ops_context * octx) {
         case HTP_OP_CUMSUM:
             return op_cumsum(octx);
 
+        case HTP_OP_DIAG:
+            return op_diag(octx);
+
         case HTP_OP_INVALID:
             break;