[MSAN] Add result printing for failed call in pthread_getaffinity_np.

Will be reverted when test failure is diagnosed. Depends on: https://reviews.llvm.org/D127185 Reviewed By: vitalybuka Differential Revision: https://reviews.llvm.org/D127320

Author: kda

compiler-rt/test/sanitizer_common/TestCases/Linux/pthread_getaffinity_np.cpp

@@ -4,13 +4,16 @@
 
 #include <assert.h>
 #include <pthread.h>
+#include <stdio.h>
 #include <sys/sysinfo.h>
 
 #include <sanitizer/msan_interface.h>
 
 int main() {
  cpu_set_t set_x;
  int res = pthread_getaffinity_np(pthread_self(), sizeof(set_x), &set_x);
+ if (res != 0)
+ printf("res: %d\n", res);
  assert(res == 0);
  assert(CPU_COUNT_S(sizeof(set_x), &set_x) == get_nprocs());