Initial Cortex R-profile support.

[alfedotov]

About year ago I had an attemp to upsream these changes. And still I see demand on such support.

[tomoveu]

+1 this looks like a great addition, considering it has no merge conflicts with master.

This would solve #314 Could someone please review this PR, @llefaucheur ?

[christophe0606]

@JonatanAntoni This is a CMSIS-Core contribution. Independent from CMSIS-DSP

[tomoveu]

@JonatanAntoni This is a CMSIS-Core contribution. Independent from CMSIS-DSP

Could you please elaborate what this means? @christophe0606

Do we have to submit these changes to a different repository or in a different manner?

[JonatanAntoni]

@tomoveu,

I guess Christophe is just wondering why I was asking him to review code in "my" area.
Your PR is totally fine here. I am just unable to confirm the code is correct. I am looking for some Cortex-R experts who can give the PR a review.

Thanks,
Jonatan

[bernardfitch]

+1 I too would like to see basic Cortex-R support like this in CMSIS-Core. I would like to encourage @christophe0606 and @llefaucheur to please review and pull these changes (if deemed appropriate) :)

If there is anything that I can do to help please let me know

(I am currently working on an R52-based chip design and continually building/testing code - coming from the M4 world it made me sad that there is no Cortex-R CMSIS code, having to revert to assembly for all but the most primitive of startup code seems like a backward step).

Bernard ;)