Fix build with WMOPS=1

• Related issues: ivas-codec-pc/ivas-codec!2434 (merged)
• Requested reviewers: @kiene

Reason why this change is needed

Compiling with make WMOPS=1 leads to a compilation error. Our CI jobs use scripts/prepare_instrumentation.sh, which activates the define directly in the code but additionally patches some other things and then compilation seems to work. For BASOP, both should be sensible use cases and should work.

Description of the change

Change the order of includes in .c source files and ensures that stl.h is included after options.h.

Affected operating points

None. It just fixes compilation with WMOPS=1.