Don't overlap STM32 FDCAN RAM sections

[jtmyz9]

Summary of changes

Shift Inital RAM Offset by index * large Number of words so that if multiple FDCAN instances created for multiple channels on STM32H7 chips they are not all pointing to the exact same CAN RAM section and sharing FIFO, filters, TX buffers, etc.

Current implementation leaves ALL FDCAN peripherals pointing to same segment of the RAM section allocated for CAN, thus messages from all the different "busses" will get pushed into same FIFO. Change makes it such that each FDCAN object actually has independent FIFOs and filters. This is acceptable because we are allocating significantly less than maximum RAM size for each instance ~306 words of maximum 2560 words

Impact of changes

Migration actions required

Documentation

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Pull request type

[x] Patch update (Bug fix / Target update / Docs update / Test update / Refactor)
[] Feature update (New feature / Functionality change / New API)
[] Major update (Breaking change E.g. Return code change / API behaviour change)

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Test results

[] No Tests required for this change (E.g docs only update)
[x] Covered by existing mbed-os tests (Greentea or Unittest)
[] Tests / results supplied as part of this PR

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Reviewers

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[jtmyz9]

Who do I need to poke to get an approving review on this PR? Would be great to get this merged 🥺

[jeromecoutant]

Who do I need to poke to get an approving review on this PR? Would be great to get this merged 🥺

@0xc0170 :-)

[jtmyz9]

Now I just need to bribe someone to run ci and merge it? 😉

[0xc0170]

I've missed to trigger CI, fixing now.

CI started

[mbed-ci]

Jenkins CI Test : ❌ FAILED

Build Number: 1 | 🔒 Jenkins CI Job | 🌐 Logs & Artifacts

CLICK for Detailed Summary

jobs	Status
jenkins-ci/mbed-os-ci_build-cloud-example-ARM	✔️
jenkins-ci/mbed-os-ci_build-cloud-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_unittests	✔️
jenkins-ci/mbed-os-ci_build-greentea-ARM	✔️
jenkins-ci/mbed-os-ci_build-greentea-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_build-example-ARM	✔️
jenkins-ci/mbed-os-ci_build-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_greentea-test	❌

[0xc0170]

CI restarted

[mbed-ci]

Jenkins CI Test : ❌ FAILED

Build Number: 2 | 🔒 Jenkins CI Job | 🌐 Logs & Artifacts

CLICK for Detailed Summary

jobs	Status
jenkins-ci/mbed-os-ci_build-cloud-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_unittests	✔️
jenkins-ci/mbed-os-ci_build-greentea-ARM	✔️
jenkins-ci/mbed-os-ci_build-cloud-example-ARM	✔️
jenkins-ci/mbed-os-ci_build-greentea-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_build-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_build-example-ARM	✔️
jenkins-ci/mbed-os-ci_greentea-test	❌

[jtmyz9]

The CI failure looks like something unrelated to this change?