Ascend Acceleration Module doc and samples

[akstt]

Thanks for your contribution and we appreciate it a lot. The following instructions would make your pull request more healthy and more easily get feedback. If you do not understand some items, don't worry, just make the pull request and seek help from maintainers.

Motivation

Add ascend acceleration module doc and samples.

Modification

• The main modification points are as follows:
  1. Create new files configs/_base_/models/ascend_retinanet_r50_fpn.py configs/_base_/models/ascend_ssd300.py configs/retinanet/ascend_retinanet_r18_fpn_1x8_1x_coco.py configs/ssd/ascend_ssd300_coco.py. Create ascend acceleration SSD module and retinanet module.
  2. Modify docs docs/en/device/npu.md docs/zh_cn/device/npu.md. Add ascend acceleration module sample description.

BC-breaking (Optional)

None.

Use cases (Optional)

None.

Checklist

• Pre-commit or other linting tools are used to fix the potential lint issues.
• The modification is covered by complete unit tests. If not, please add more unit test to ensure the correctness.
• If the modification has potential influence on downstream projects, this PR should be tested with downstream projects, like MMDet or MMCls.
• The documentation has been modified accordingly, like docstring or example tutorials.

[codecov]

Codecov Report

Base: 64.41% // Head: 64.45% // Increases project coverage by +0.03% 🎉

Coverage data is based on head (1a6ae36) compared to base (9054e4c).
Patch has no changes to coverable lines.

Additional details and impacted files

@@            Coverage Diff             @@
##              dev    #9648      +/-   ##
==========================================
+ Coverage   64.41%   64.45%   +0.03%     
==========================================
  Files         370      370              
  Lines       30032    30032              
  Branches     5007     5007              
==========================================
+ Hits        19346    19358      +12     
+ Misses       9650     9637      -13     
- Partials     1036     1037       +1     

Flag	Coverage Δ
unittests	64.44% <ø> (+0.03%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
mmdet/models/dense_heads/corner_head.py	69.72% <0.00%> (+1.38%)	⬆️
mmdet/utils/misc.py	64.44% <0.00%> (+2.22%)	⬆️
mmdet/core/bbox/assigners/sim_ota_assigner.py	83.63% <0.00%> (+3.63%)	⬆️
mmdet/models/detectors/cornernet.py	100.00% <0.00%> (+5.12%)	⬆️

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

☔ View full report at Codecov.
📢 Do you have feedback about the report comment? Let us know in this issue.