HAL CRC: Remove testing section from porting guide until tests are added

Author: Steven Cartmell

docs/reference/contributing/target/crc.md

@@ -32,17 +32,3 @@ You can find the API and specification for the hardware CRC API in the following
 [![View code](https://www.mbed.com/embed/?type=library)](http://os-doc-builder.test.mbed.com/docs/development/mbed-os-api-doxy/group__hal__crc.html)
 
 To enable hardware CRC support in Mbed OS, add the `CRC` label in the `device_has` option of the target's section in the `targets.json` file.
-
-#### Testing
-
-The Mbed OS HAL API provides a set of conformance tests for Hardware CRC. You can use these tests to validate the correctness of your implementation. To run the hardware CRC HAL tests, use the following command:
-
-```
-mbed test -t <toolchain> -m <target> -n "tests-mbed_hal-crc*"
-```
-
-You can read more about the test cases here:
-
-```
-Fix link after code is merged.
-```