LoongArch: BPF: Use move_addr() for BPF_PSEUDO_FUNC

Vincent reported that running XDP synproxy program on LoongArch
results in the following error:
    JIT doesn't support bpf-to-bpf calls
With dmesg:
    multi-func JIT bug 1391 != 1390

The root cause is that verifier will refill the imm with the
correct addresses of bpf_calls for BPF_PSEUDO_FUNC instructions
and then run the last pass of JIT. So we generate different JIT
code for the same instruction in two passes (one for placeholder
and one for real address). Let's use move_addr() instead.

See commit 64f50f6 ("LoongArch, bpf: Use 4 instructions for
 function address in JIT") for a similar fix.

Fixes: 69c087b ("bpf: Add bpf_for_each_map_elem() helper")
Fixes: bb035ef ("LoongArch: BPF: Support mixing bpf2bpf and tailcalls")
Reported-by: Vincent Li <vincent.mc.li@gmail.com>
Closes: https://lore.kernel.org/loongarch/CAK3+h2yfM9FTNiXvEQBkvtuoJrvzmN4c_NZsFXqEk4Cj1tsBNA@mail.gmail.com/T/#u
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Tested-by: Vincent Li <vincent.mc.li@gmail.com>

Author: chenhengqi

arch/loongarch/net/bpf_jit.c

@@ -930,7 +930,10 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext
 	{
 		const u64 imm64 = (u64)(insn + 1)->imm << 32 | (u32)insn->imm;
 
-		move_imm(ctx, dst, imm64, is32);
+		if (bpf_pseudo_func(insn))
+			move_addr(ctx, dst, imm64);
+		else
+			move_imm(ctx, dst, imm64, is32);
 		return 1;
 	}