drivers: modem: fix uninitialized variables

[FKainka]

This PR is related to the following Zephyr PR:
#81431 Some compilers (e.g. arm-zephyr-eabi-gcc) don't understand the K_SPINLOCK() macro and therefore do warn about uninitialized variables in the modem related modules.

Signed-off-by: Fabian Kainka [email protected]

[github-actions]

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[bjarki-andreasen]

could you instead replace the K_SPINLOCK macros with the "normal" lock+unlock calls? initializing the variables uses more ROM, so its not free to initialize them :)

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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