helper_access_check_cp_reg() raising Undefined Instruction on big-endian host

As of commit 222059a0, when running the Avocado test from commit 27dfbafa ("tests/acceptance: Add a boot test for the xlnx-versal-virt machine") on a s390x host, I get:

$ gdb -q ./qemu-system-aarch64
(gdb) b raise_exception if target_el==2
(gdb) r -display none -machine xlnx-versal-virt -m 2G -accel tcg -kernel ~/avocado/data/cache/by_location/86dbba0cf1f2cb724a2a5a3f3b29eb4126f52d45/linux -initrd ~/avocado/data/cache/by_location/86dbba0cf1f2cb724a2a5a3f3b29eb4126f52d45/initrd.gz -serial mon:stdio -d in_asm -trace memory\* -d int,in_asm
[...]
----------------
IN: 
0xffff000008990268:  a9bf7bfd  stp      x29, x30, [sp, #-0x10]!
0xffff00000899026c:  910003fd  mov      x29, sp
0xffff000008990270:  aa1e03e0  mov      x0, x30
0xffff000008990274:  d503201f  nop      
0xffff000008990278:  d53be220  mrs      x0, cntp_ctl_el0
0xffff00000899027c:  927f7800  and      x0, x0, #0xfffffffe
0xffff000008990280:  d51be220  msr      cntp_ctl_el0, x0

[Switching to Thread 0x3ffea9bf900 (LWP 3773576)]

Thread 3 "qemu-system-aar" hit Breakpoint 17, raise_exception (env=env@entry=0x3ffeaab3540, excp=excp@entry=1, syndrome=syndrome@entry=1647507461, target_el=2)
    at ../../target/arm/op_helper.c:49
49	    CPUState *cs = env_cpu(env);
(gdb) bt
#0  raise_exception (env=env@entry=0x3ffeaab3540, excp=excp@entry=1, syndrome=syndrome@entry=1647507461, target_el=2) at ../../target/arm/op_helper.c:49
#1  0x000002aa007f3f52 in helper_access_check_cp_reg (env=0x3ffeaab3540, rip=0x2aa01c394f0, syndrome=1647507461, isread=<optimized out>) at ../../target/arm/op_helper.c:705
#2  0x000003ffa45ba2c8 in code_gen_buffer ()
#3  0x000002aa00ae9c62 in cpu_tb_exec (tb_exit=<synthetic pointer>, itb=0x3ffa45ba100 <code_gen_buffer+6004964>, cpu=<optimized out>) at ../../accel/tcg/cpu-exec.c:438
#4  cpu_loop_exec_tb (tb_exit=<synthetic pointer>, last_tb=<synthetic pointer>, pc=<optimized out>, tb=0x3ffa45ba100 <code_gen_buffer+6004964>, cpu=<optimized out>)
    at ../../accel/tcg/cpu-exec.c:868
#5  cpu_exec (cpu=<optimized out>) at ../../accel/tcg/cpu-exec.c:1032
#6  0x0000000000000400 in  ()
(gdb) c
Continuing.
Taking exception 1 [Undefined Instruction] on CPU 0
...from EL1 to EL2
...with ESR 0x18/0x6232f805
...with ELR 0xffff000008990278
...to EL2 PC 0xb66400 PSTATE 0x3c9

It works fine on x86_64 host.