Removed gcc_builtins as the "real" builtins have been found.
Simulator now builds with SSE2 support.
idMatX::CopyLowerToUpperTriangle now builds with SSE on x86.
Defines more accurately determine intrinsic support
qnx_cpu now fully supports Sys_GetCPUId for both ARM and x86.
Implemented idMatX::CopyLowerToUpperTriangle for ARM NEON
Made sure x86 defines for intrinsics are used