[PATCH] tracing/probes: Mark expected switch fall-through

["Gustavo A. R. Silva" <gustavo@embeddedor.com>]

In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warning:

kernel/trace/trace_probe.c: In function ‘parse_probe_arg’:
kernel/trace/trace_probe.c:302:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
   arg++; /* Skip '+', because kstrtol() rejects it. */
   ~~~^~
kernel/trace/trace_probe.c:303:2: note: here
  case '-':
  ^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
 kernel/trace/trace_probe.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 9962cb5da8ac..89da34b326e3 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -300,6 +300,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
 
 	case '+':	/* deref memory */
 		arg++;	/* Skip '+', because kstrtol() rejects it. */
+		/* fall through */
 	case '-':
 		tmp = strchr(arg, '(');
 		if (!tmp)
-- 
2.20.1