mprotect: fix mapEntrySplit

[badochov]

Do not call amap_getanons. Set offset and lmaxgap.

JIRA: RTOS-895

Description

Motivation and Context

Types of changes

• [x] 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.

[github-actions[bot]]

Unit Test Results

5 244 tests   - 2 456   4 778 :white_check_mark:  - 2 207   19m 0s :stopwatch: - 18m 19s   280 suites  -   156     466 :zzz:  -   249      1 files   ±    0       0 :x: ±    0 

Results for commit eb984f1e. ± Comparison against base commit dadb7d50.

This pull request removes 2456 tests.

``` flash ‑ armv7a7-imx6ull-evk:flash flash ‑ armv7m4-stm32l4x6-nucleo:flash flash ‑ riscv64-generic-qemu:flash phoenix-rtos-tests/cpp/hello-cpp ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/cpp/hello-cpp phoenix-rtos-tests/cpp/hello-cpp ‑ riscv64-generic-qemu:phoenix-rtos-tests/cpp/hello-cpp phoenix-rtos-tests/initfini/main ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/initfini/main phoenix-rtos-tests/initfini/main ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/initfini/main phoenix-rtos-tests/initfini/main ‑ riscv64-generic-qemu:phoenix-rtos-tests/initfini/main phoenix-rtos-tests/ioctl/unit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/ioctl/unit.ioctl.data_in phoenix-rtos-tests/ioctl/unit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/ioctl/unit.ioctl.data_in_big … ```

:recycle: This comment has been updated with latest results.