tools/sched_ext: Sync README.md Kconfig with upstream scx

Sync the documentation with the upstream scx repository to
reflect the current recommended configuration.

Ref: https://github.com/sched-ext/scx/blob/main/README.md#build--install

Signed-off-by: Cheng-Yang Chou <yphbchou0911@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Author: EricccTaiwan

tools/sched_ext/README.md

@@ -58,14 +58,8 @@ CONFIG_SCHED_CLASS_EXT=y
 CONFIG_BPF_SYSCALL=y
 CONFIG_BPF_JIT=y
 CONFIG_DEBUG_INFO_BTF=y
-```
-
-It's also recommended that you also include the following Kconfig options:
-
-```
 CONFIG_BPF_JIT_ALWAYS_ON=y
 CONFIG_BPF_JIT_DEFAULT_ON=y
-CONFIG_PAHOLE_HAS_BTF_TAG=y
 ```
 
 There is a `Kconfig` file in this directory whose contents you can append to