Make generic.cmake no longer depend on util.cmake

[wangkuiyi]

Fixes #2324
Fixes #2223
Fixes #2322
Fixes #2321

I tested this PR by

1. starting a development container

   cd ~/work/paddle
   git checkout develop 
   git pull
   docker build -t paddle:dev .
   docker run --rm -it -v $PWD:/paddle paddle:dev /bin/bash

   and

2. build paddle/majel inside the container

   cd /paddle/build
   rm CMakeCache*
   cmake -DCUDNN_ROOT=/usr ..
   make -j place_test ddim_test dim_test cuda_test
   ctest -R place_test
   ctest -R ddim_test

[wangkuiyi]

@gangliao Some my ideas for the future noted at #2327. Could you please read and verify?

[helinwang]

LGTM! Thank you!

[gangliao]

LGTM