[PATCH v2 5.15.y 0/2] bpf: fix warning in ftrace_verify_code()

This bug was found by syzkaller.

The reproducer and the detailed warning log can be viewed here [1]

[1] https://lore.kernel.org/bpf/20240129091746.260538-1-kovalev@altlinux.org/#t

Capability cap_sys_admin is required for reproduce and on kernels with panic_on_warn enabled it will cause the system to crash.

v2: Added an additional patch that fixes a build error by the clang compiler.

To solve the problem, it is proposed to backport the following commits:

[PATCH v2 5.15.y 1/2] bpf: Convert BPF_DISPATCHER to use static_call() (not [PATCH v2 5.15.y 2/2] bpf: Add explicit cast to 'void *' for