bpf: kprobe: Remove unused declaring of bpf_kprobe_override

bpf: kprobe: Remove unused declaring of bpf_kprobe_override

After the commit 66665ad2f102 ("tracing/kprobe: bpf: Compare instruction
pointer with original one"), "bpf_kprobe_override" is not used anywhere
anymore, and we can remove it now.

Fixes: 66665ad2f102 ("tracing/kprobe: bpf: Compare instruction pointer with original one")
Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240730053733.885785-1-dongml2@chinatelecom.cn