[PATCH] perf/core: 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/events/core.c: In function ‘perf_event_parse_addr_filter’:
kernel/events/core.c:9154:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
    kernel = 1;
    ~~~~~~~^~~
kernel/events/core.c:9156:3: note: here
   case IF_SRC_FILEADDR:
   ^~~~

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/events/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index ac194d3aae32..343ee21ab958 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -9152,6 +9152,7 @@ perf_event_parse_addr_filter(struct perf_event *event, char *fstr,
 		case IF_SRC_KERNELADDR:
 		case IF_SRC_KERNEL:
 			kernel = 1;
+			/* fall through */
 
 		case IF_SRC_FILEADDR:
 		case IF_SRC_FILE:
-- 
2.20.1