vm/map: fix shared maps allocated calculation

[etiaro]

Description

Implementation was overestimating allocated memory when map memory was fragmented.

TASK: RTOS-1345

Motivation and Context

The result is used in psh mem -s command.

Types of changes

• 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)
• Chore (refactoring, style fixes, git/CI config, submodule management, no code logic changes)

How Has This Been Tested?

• Already covered by automatic testing.
• New test added: (add PR link here).
• Tested by hand on: (list targets here).

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing linter checks and tests passed.
• My changes generate no new compilation warnings for any of the targets.

Special treatment

• This PR needs additional PRs to work (list the PRs, preferably in merge-order).
• I will merge this PR by myself when appropriate.

[gemini-code-assist]

Code Review

This pull request updates the free memory calculation in vm/map.c by locking the map and iterating through all of its entries to subtract their sizes from the total map size. The review feedback points out that casting e->size to an int during this subtraction is unnecessary and risks integer truncation or overflow on systems with large mappings, suggesting direct subtraction instead.

Important

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[github-actions]

Unit Test Results

10 860 tests  +275   10 190 ✅ +275   53m 3s ⏱️ +55s
   670 suites + 21      670 💤 ±  0 
     1 files   ±  0        0 ❌ ±  0 

Results for commit 9014bf3. ± Comparison against base commit 57b3041.

This pull request removes 3 and adds 278 tests. Note that renamed tests count towards both.

phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit
phoenix-rtos-tests/libcache/unit ‑ armv7m7-imxrt106x-evk:phoenix-rtos-tests/libcache/unit
phoenix-rtos-tests/libcache/unit ‑ armv7m7-imxrt117x-evk:phoenix-rtos-tests/libcache/unit

phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit.test_callback_err.cache_cleanCallbackErr
phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit.test_callback_err.cache_flushCallbackErr
phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit.test_callback_err.cache_read_readCallbackErr
phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit.test_callback_err.cache_write_readCallbackErr
phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit.test_callback_err.cache_write_writeCallbackErr
phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit.test_clean.cache_clean_addrOutOfScope
phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit.test_clean.cache_clean_addrPartiallyInScope
phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit.test_clean.cache_clean_badAddrRange
phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit.test_clean.cache_clean_lines
phoenix-rtos-tests/libcache/unit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libcache/unit.test_deinit.cache_deinit_initalizedCache
…