tracing: Remove __idx variable from __DO_TRACE

Since the removal of SRCU-protected tracepoints, the __idx variable in
__DO_TRACE is unused. Remove this variable.

Fixes: 48bcda6 ("tracing: Remove definition of trace_*_rcuidle()")
Cc: Linus Torvalds <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Michael Jeanson <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Yonghong Song <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: [email protected]
Cc: Joel Fernandes <[email protected]>
Cc: Jordan Rife <[email protected]>
Link: https://lore.kernel.org/[email protected]
Signed-off-by: Mathieu Desnoyers <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

Author: compudj

include/linux/tracepoint.h

@@ -218,8 +218,6 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p)
  */
 #define __DO_TRACE(name, args, cond, syscall)				\
 	do {								\
-		int __maybe_unused __idx = 0;				\
-									\
 		if (!(cond))						\
 			return;						\
 									\