[openmp] Add amdgpu impl missed from D112153

GitOrigin-RevId: cf37a94c1e42ce5b6eff272098c678c021c46c3b
diff --git a/libomptarget/DeviceRTL/src/Synchronization.cpp b/libomptarget/DeviceRTL/src/Synchronization.cpp
index 33e2194..931dffc 100644
--- a/libomptarget/DeviceRTL/src/Synchronization.cpp
+++ b/libomptarget/DeviceRTL/src/Synchronization.cpp
@@ -192,6 +192,7 @@
 }
 
 void syncThreads() { __builtin_amdgcn_s_barrier(); }
+void syncThreadsAligned() { syncThreads(); }
 
 // TODO: Don't have wavefront lane locks. Possibly can't have them.
 void unsetLock(omp_lock_t *) { __builtin_trap(); }