bcache: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1].

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by Gustavo A. R. Silva <[email protected]>

---
Changes in v2:
- Add missing semicolon.

 drivers/md/bcache/journal.c |  2 +-
 drivers/md/bcache/util.c    | 14 +++++++-------
 2 files changed, 8 insertions(+), 8 deletions(-)

drivers/md/bcache/journal.c +1 -1

index 77fbfd52edcf..c1227bdb57e7 100644
@@ -608,7 +608,7 @@ static void do_journal_discard(struct cache *ca)
 			ca->sb.njournal_buckets;
 
 		atomic_set(&ja->discard_in_flight, DISCARD_READY);
-		/* fallthrough */
+		fallthrough;
 
 	case DISCARD_READY:
 		if (ja->discard_idx == ja->last_idx)

drivers/md/bcache/util.c +7 -7

index 62fb917f7a4f..ae380bc3992e 100644
@@ -33,27 +33,27 @@ int bch_ ## name ## _h(const char *cp, type *res)		\
 	case 'y':						\
 	case 'z':						\
 		u++;						\
-		/* fall through */				\
+		fallthrough;					\
 	case 'e':						\
 		u++;						\
-		/* fall through */				\
+		fallthrough;					\
 	case 'p':						\
 		u++;						\
-		/* fall through */				\
+		fallthrough;					\
 	case 't':						\
 		u++;						\
-		/* fall through */				\
+		fallthrough;					\
 	case 'g':						\
 		u++;						\
-		/* fall through */				\
+		fallthrough;					\
 	case 'm':						\
 		u++;						\
-		/* fall through */				\
+		fallthrough;					\
 	case 'k':						\
 		u++;						\
 		if (e++ == cp)					\
 			return -EINVAL;				\
-		/* fall through */				\
+		fallthrough;					\
 	case '\n':						\
 	case '\0':						\
 		if (*e == '\n')					\