mimxrt1020_evk samples/net/zperf meets Unaligned memory access

[hakehuang]

Describe the bug
Unaligned memory access

To Reproduce
Steps to reproduce the behavior:

1. mkdir build; cd build
2. cmake -DBOARD=mimxrt1020_evk ..
3. make
4. make flash

Expected behavior
sample can run with perf data

Impact
net performance result

Screenshots or console output

***** USAGE FAULT *****

  Unaligned memory access

***** Hardware exception *****

Current thread ID = 0x80002cf8

Faulting instruction address = 0x6001a9ee

Fatal fault in essential thread! Spinning...

Environment (please complete the following information):

• OS: Linux,
• Toolchain (Zephyr SDK, ...)
• Commit SHA or Version used: v1.14.0_rc1

[hakehuang]

@MaureenHelm

[hakehuang]

same root cause as #13727