(allocate_pseudovector): New fun.

(allocate_pseudovector): New fun.
(ALLOCATE_PSEUDOVECTOR): New macro.
(allocate_window, allocate_terminal, allocate_frame)
(allocate_process): Use it.
(mark_vectorlike): New function.
(mark_object) <FRAMEP, WINDOWP, BOOL_VECTOR_P, VECTORP>: Use it.
(mark_terminals): Use it.
(Fmake_bool_vector, Fmake_char_table, make_sub_char_table)
(Fmake_byte_code): Use XSETPVECTYPE.