Fix bug where openblas_set_threads_callback_function does not support modyfing symbol prefix and suffix in shared library

[lujiaweics]

No description provided.

[martin-frbg]

thank you

[al3xtjames]

Should these symbols be limited to multithreaded builds? I'm seeing this error while trying to build a single-threaded build on macOS:

Undefined symbols for architecture x86_64:
  "_openblas_set_threads_callback_function", referenced from:
     -exported_symbol[s_list] command line option
ld: symbol(s) not found for architecture x86_64
collect2: error: ld returned 1 exit status
make[1]: *** [Makefile:166: libopenblas-r0.3.31.dylib] Error 1
make[1]: Leaving directory '/nix/var/nix/b/20zrcf6cgm5ah1rq0f4byy2dcm/source/exports'
make: *** [Makefile:158: shared] Error 2

It looks like this is because blas_server_callback.c (which defines openblas_set_threads_callback_function) is only built if multithreading is enabled:

OpenBLAS/driver/others/Makefile

Lines 8 to 13 in 45e9820

	ifdef SMP
	COMMONOBJS += blas_server.$(SUFFIX) divtable.$(SUFFIX) blasL1thread.$(SUFFIX) blas_server_callback.$(SUFFIX)
	ifneq ($(NO_AFFINITY), 1)
	COMMONOBJS += init.$(SUFFIX)
	endif
	endif