llvm: Fixed remaining warnings for llvm

This commit addresses warnings emitted from the llvm
compilers which were not encountered with gnu.

Signed-off-by: Noel Eck <noel.eck@intel.com>

src/am2315/am2315.hpp

@@ -197,7 +197,6 @@ class AM2315 {
         time_t    m_last_time;
 
         int       m_base_priority;
-        pthread_t this_thread;
 };
 
 }