canisotp: mimxrt1064_evk: no DT_CHOSEN_ZEPHYR_CAN_PRIMARY_LABEL defined cause tests failure

[hakehuang]

Describe the bug
the can.isotp test cases use the DT_CHOSEN_ZEPHYR_CAN_PRIMARY_LABEL as default test devices, but for NXP RT series boards those are not defined.

To Reproduce
Steps to reproduce the behavior:
cd to tests/subsys/canbus/isotp/conformance

1. mkdir build; cd build
2. cmake -DBOARD=mimxrt1064_evk ..
3. make
4. See error

Expected behavior
can test can run

Impact
can usage

Logs and console output

 *** Booting Zephyr OS version 2.4.99  ***
    
        Assertion failed at WEST_TOPDIR/zephyr/tests/subsys/canbus/isotp/conformance/src/main.c:883: test_main: (can_dev is NULL)
    CAN device not not found
    ASSERTION FAIL [!(thread->base.user_options & ((1UL << (0))))] @ WEST_TOPDIR/zephyr/kernel/sched.c:512
    	essential thread aborted
    E: r0/a1:  0x00000004  r1/a2:  0x00000200  r2/a3:  0x00800000
    E: r3/a4:  0x70004591 r12/ip:  0x00000000 r14/lr:  0x70008b43
    E:  xpsr:  0x61000000
    E: Faulting instruction address (r15/pc): 0x7000aaf0
    E: >>> ZEPHYR FATAL ERROR 4: Kernel panic on CPU 0
    E: Current thread: 0x800004e8 (idle 00)
    E: Halting system

Environment (please complete the following information):

• OS: (e.g. Linux)
• Toolchain (e.g Zephyr SDK, ...)
• Commit SHA or Version used: 2.4.99