Changed 'rtl/pcie_tlp_fifo_raw.v' according to IEEE-1800-2017.

Chapter 11.5.1: ... logic [15:0] down_vect; logic [0:15] up_vect; down_vect[lsb_base_expr +: width_expr] up_vect[msb_base_expr +: width_expr] down_vect[msb_base_expr -: width_expr]

The msb_base_expr and lsb_base_expr shall be integer expressions, and the width_expr shall be a positive constant integer expression.

Signed-off-by: Ivan Grigorov grigorovia@ispras.ru