add llvm Intrinsic call support.
add llvm Intrinsic call support.

so far this patch only support uadd_with_overflow.
sadd_with_overflow, usub_with_overflow, smul_with_overflow, umul_with_overflow, bswap are not supported yet.
this funtion should be implemented by carrier flag later.

v2: update comments.

Signed-off-by: Luo Xionghu <c3dafbeb50547b880155fb36e6f40d38b44f6611@intel.com>
Reviewed-by: Zhigang Gong <e04a7b9b70b1e4c6318cf117dcd1a9056e14b97a@linux.intel.com>

zhenyw/beignet,zhenyw/beignet,wdv4758h/beignet,freedesktop-unofficial-mirror/beignet,zhenyw/beignet,freedesktop-unofficial-mirror/beignet,wdv4758h/beignet,freedesktop-unofficial-mirror/beignet,zhenyw/beignet,wdv4758h/beignet,wdv4758h/beignet,freedesktop-unofficial-mirror/beignet,wdv4758h/beignet,zhenyw/beignet