tests: mheap_api_concept: fix non-reentrant thread_id

in test case test_mheap_threadsafe, we will create 3 threads using
same thread handler tmheap_handler, we should make thread_id
to be a local variable, otherwise tmheap_handler is non-reentrant.

Signed-off-by: Watson Zeng <zhiwei@synopsys.com>
1 file changed