sparcv8leon3: fix strncpy implementation

[lukileczo]

JIRA: RTOS-693

Description

Issue found when running tests

Motivation and Context

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)

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]

Unit Test Results

5 199 tests   - 796   4 647 ✔️  - 707   26m 57s ⏱️ - 1m 52s
   298 suites  -   41      551 💤  -   90 
       1 files   ±    0          1 ❌ +    1 

For more details on these failures, see this check.

Results for commit a767441. ± Comparison against base commit 0ff64df.

This pull request removes 802 and adds 6 tests. Note that renamed tests count towards both.

phoenix-rtos-tests/cpp/hello-cpp ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/cpp/hello-cpp
phoenix-rtos-tests/initfini/main ‑ armv7a7-imx6ull-evk: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
phoenix-rtos-tests/ioctl/unit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/ioctl/unit.ioctl.data_inout
phoenix-rtos-tests/ioctl/unit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/ioctl/unit.ioctl.data_inout_big
phoenix-rtos-tests/ioctl/unit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/ioctl/unit.ioctl.data_out
phoenix-rtos-tests/ioctl/unit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/ioctl/unit.ioctl.data_out_big
phoenix-rtos-tests/ioctl/unit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/ioctl/unit.ioctl.in_val
phoenix-rtos-tests/ioctl/unit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/ioctl/unit.ioctl.invalid_req
…

phoenix-rtos-tests/psh/exit ‑ armv7a9-zynq7000-qemu:phoenix-rtos-tests/psh/exit
phoenix-rtos-tests/psh/exit ‑ armv7a9-zynq7000-zedboard:phoenix-rtos-tests/psh/exit
phoenix-rtos-tests/psh/exit ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/psh/exit
phoenix-rtos-tests/psh/exit ‑ armv7m7-imxrt106x-evk:phoenix-rtos-tests/psh/exit
phoenix-rtos-tests/psh/exit ‑ ia32-generic-qemu:phoenix-rtos-tests/psh/exit
phoenix-rtos-tests/psh/exit ‑ riscv64-generic-qemu:phoenix-rtos-tests/psh/exit