fgraph: Remove some unused functions

fgraph: Remove some unused functions

These functions are defined in the fgraph.c file, but not
called elsewhere, so delete these unused functions.

kernel/trace/fgraph.c:273:1: warning: unused function 'set_bitmap_bits'.
kernel/trace/fgraph.c:259:19: warning: unused function 'get_fgraph_type'.

Link: https://lore.kernel.org/linux-trace-kernel/20240606021053.27783-1-jiapeng.chong@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=9289
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>