rockchip: tinker-rk3288: Use common BOOT_TARGET_DEVICES

rockchip: tinker-rk3288: Use common BOOT_TARGET_DEVICES

Building U-Boot for Tinker Board with USB or NET Kconfig option disabled
result in the following build error:

  In file included from include/configs/rk3288_common.h:29,
                   from include/configs/tinker_rk3288.h:14,
                   from include/config.h:3,
                   from include/common.h:16,
                   from env/common.c:10:
  include/config_distro_bootcmd.h:302:9: error: expected '}' before 'BOOT_TARGET_DEVICES_references_USB_without_CONFIG_CMD_USB'
    302 |         BOOT_TARGET_DEVICES_references_USB_without_CONFIG_CMD_USB
        |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  include/config_distro_bootcmd.h:302:9: note: in definition of macro 'BOOTENV_DEV_NAME_USB'
    302 |         BOOT_TARGET_DEVICES_references_USB_without_CONFIG_CMD_USB
        |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  include/configs/tinker_rk3288.h:21:9: note: in expansion of macro 'BOOTENV_DEV_NAME'
     21 |         func(USB, usb, 0) \
        |         ^~~~
  include/config_distro_bootcmd.h:454:25: note: in expansion of macro 'BOOT_TARGET_DEVICES'
    454 |         "boot_targets=" BOOT_TARGET_DEVICES(BOOTENV_DEV_NAME) "\0"
        |                         ^~~~~~~~~~~~~~~~~~~
  include/config_distro_bootcmd.h:474:9: note: in expansion of macro 'BOOTENV_BOOT_TARGETS'
    474 |         BOOTENV_BOOT_TARGETS \
        |         ^~~~~~~~~~~~~~~~~~~~
  include/configs/rk3288_common.h:40:9: note: in expansion of macro 'BOOTENV'
     40 |         BOOTENV
        |         ^~~~~~~
  include/env_default.h:122:9: note: in expansion of macro 'CFG_EXTRA_ENV_SETTINGS'
    122 |         CFG_EXTRA_ENV_SETTINGS
        |         ^~~~~~~~~~~~~~~~~~~~~~
  In file included from env/common.c:32:
  include/env_default.h:29:36: note: to match this '{'
     29 | const char default_environment[] = {
        |                                    ^
  make[2]: *** [scripts/Makefile.build:256: env/common.o] Error 1

The BOOT_TARGET_DEVICES defined in rockchip-common.h include the same
devices as defined in tinker_rk3288.h, remove the board specific one to
fix building with USB or NET option disabled.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>