dual: run host_info_to_device_cdc on ea4088_quickstart

The board has both USB ports wired: U1 to the Type-A host connector and U2
to the micro-B device connector, and board_init() already puts the port
select in that mode, so it can run the dual example.

- Allow the example on LPC40XX.
- Point the host stack at rhport 0: ohci maps the TinyUSB rhport onto its
  root-hub port index, and the host controller here is index 0, while the
  dual examples default to rhport 1.
- Move the string-descriptor buffers out of the stack. They are written by
  the host controller, so on parts whose USB master cannot reach the CPU
  stack (this family) the strings came back as garbage. host/device_info
  already keeps its transfer buffer in CFG_TUH_MEM_SECTION; do the same
  here.

Verified on ea4088_quickstart with a WCH-Link on the Type-A port and the
micro-B plugged into a PC:

  mounted device 1
  Device 1: ID 1a86:8010 SN 7FD88F0604B5
    iManufacturer       1     wch.cn
    iProduct            2     WCH-Link