Modify all the builtin function vect return to (vect_name)(e1, e2, e3)

Modify all the builtin function vect return to (vect_name)(e1, e2, e3)

Some builtin functions has the prototype like:
int3 function_name (int3 x) { return (x.s0, x.s1, x.s2);}
which not comply with CL spec and will cause the clang IR
be translated error.
The vector declare should be (vect)(e1, e2, e3)

Signed-off-by: Junyan He <junyan.he@linux.intel.com>
Reviewed-by: Zhigang Gong <zhigang.gong@linux.intel.com>