pcsx2: replace memset_sse_a by standard memset

Code is only enabled in dev build.

In the future allocation (therefore the memset) will be done at startup anyway.

pcsx2/System.cpp

@@ -100,7 +100,7 @@ void RecompiledCodeReserve::OnCommittedBlock( void* block )
 		// the assembly dump more cleanly.  We don't clear the block on Release builds since
 		// it can add a noticeable amount of overhead to large block recompilations.
 
-		memset_sse_a<0xcc>( block, m_blocksize * __pagesize );
+		memset(block, 0xCC, m_blocksize * __pagesize);
 	}
 }