[Bug] relay parser not support var name contain "/"

[sleepcoo]

def test_simple():
    code = """
#[version = "0.0.5"]
def @simple[A, B](%fdd/ddsa: fn(A) -> B, %xs: A) -> B {
  %fdd/ddsa(%xs)
}
def @main(%l: Tensor[(5, 5), float32]) -> Tensor[(5, 5), float32] {
  %0 = fn[A](%x: A) -> A {
    %x
  };
  @simple(%0, %l)
}
"""
    # error
    mod = tvm.parser.fromtext(code)