ring-buffer: Remove the unused variable bmeta

Variable bmeta is not effectively used, so delete it.

kernel/trace/ring_buffer.c:1952:27: warning: variable ‘bmeta’ set but not used.

Link: https://lore.kernel.org/20250317015524.3902-1-jiapeng.chong@linux.alibaba.com


Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=19524


Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>