dnn: add the CANN backend (#22634)

* cann backend impl v1

* cann backend impl v2: use opencv parsers to build models for cann

* adjust fc according to the new transA and transB

* put cann net in cann backend node and reuse forwardLayer

* use fork() to create a child process and compile cann model

* remove legacy code

* remove debug code

* fall bcak to CPU backend if there is one layer not supoorted by CANN backend

* fix netInput forward

cmake/checks/cann.cpp

@@ -0,0 +1,20 @@
+#include <acl/acl.h>
+#include <unistd.h> // fork()
+#include <iostream>
+
+int main(int /*argc*/, char** /*argv*/)
+{
+    int ret = aclInit(NULL);
+    if (ret != 0)
+    {
+        std::cerr << "Failed to initialize Ascend, ret = " << ret;
+    }
+
+    ret = aclFinalize();
+    if (ret != 0)
+    {
+        std::cerr << "Failed to de-initialize Ascend, ret = " << ret;
+    }
+
+    return 0;
+}