bpf, arm64: Remove duplicated bpf_flush_icache()

The bpf_flush_icache() is done by bpf_arch_text_copy() already.
Remove the duplicated one in arch_prepare_bpf_trampoline().

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Acked-by: Puranjay Mohan <puranjay@kernel.org>
Link: https://lore.kernel.org/r/20250904075703.49404-1-hengqi.chen@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Author: chenhengqi

arch/arm64/net/bpf_jit_comp.c

@@ -2773,7 +2773,6 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
 		goto out;
 	}
 
-	bpf_flush_icache(ro_image, ro_image + size);
 out:
 	kvfree(image);
 	return ret;