tests: kernel: fix two semaphroe testcases failed on ADSP

Two testcases of semaphore failed in ADSP due to the timeout value
we got back from the child thread is invalid. We put the variable in
the bss instead of in a stack, trying to avoid this.

Fixes #34687

Signed-off-by: Enjia Mai <enjiax.mai@intel.com>
1 file changed