Improve heap definition

[josesimoes]

Description

• CRT heap now has defined size (was managed Heap).
• Update linker and rules files accordingly.

Motivation and Context

• The previous approach had a defined size for the managed Heap (defined as a linker symbol). The CRT heap was taking the available RAM left from all the other region assignments.
  This approach required an adjustment (increase) of the managed Heap as more features where added to the image. The need for this manual adjustment prevented the automated resize of the available RAM for the managed heap, which is a poor solution.
  Moreover there was an issue with the managed heap definition that was wrongly setting the region start to the RAM start.

How Has This Been Tested?

Image compiled and tested with Blinky on several reference boards.

Screenshots

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Signed-off-by: José Simões jose.simoes@eclo.solutions

[nfbot]

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Thank you for your contribution!

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