ANDROID: Delete some build configs from build.config.common.

- EXTRA_CMDS: Not used by Kleaf.

- STOP_SHIP_TRACEPRINTK: Not used by Kleaf. If we need this feature,
  we should implement it in Kleaf separately.

- IN_KERNEL_MODULES: Not used by Kleaf. We always install modules
  as part of the kernel_modules()/kernel_modules_install() rule.

- DO_NOT_STRIP_MODULES: Not used by Kleaf.
  - kernel_build relies on the strip_modules attribute and does not
    rely on the value of this.
  - system_dlkm/vendor_dlkm unset its value and does not respect
    the value of this.

- HERMETIC_TOOLCHAIN: Not used by Kleaf; kernel_env() always uses
  hermetic toolchain regardless of its value.

Bug: 236012223
Change-Id: I23b9093152b502aeb60fa478036fc8df54a56bbd
Signed-off-by: HONG Yifan <elsk@google.com>