[STM32L4R5ZI]: gdb-multiarch uses wrong osabi

[bauen1]

• I made serious effort to avoid creating duplicate or nearly similar issue

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• Programmer/board type: Unsure/STM32L4R5ZI Nucleo
• Operating system an version: Linux
• stlink tools version and/or git commit hash: v1.8.0
• stlink commandline tool name: st-util
• Target chip (and board, if applicable): Unsure

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Commandline output:

(gdb) target extended-remote localhost:4242
Remote debugging using localhost:4242
[[REDACTED]]
(gdb) show osabi 
The current OS ABI is "auto" (currently "GNU/Linux").
The default OS ABI is "GNU/Linux".

Expected/description:

I would expect gdb to detect the osabi and set it e.g. to none, this is seemingly important, so that single stepping works, otherwise when stepping displacements will use ARM instructions instead of Thumb instructions, causing hard faults when stepping into the SRAM memory.

I am not sure, but by setting the osabi in the xml st-util provides to gdb, this should be set automatically.
I'll try and test that tomorrow and make a MR, should only take an hour or so.