[PATCH v2][next] mtd: rawnand: stm32_fmc2: Fix fall-through warnings for Clang

In preparation to enable -Wimplicit-fallthrough for Clang, fix a couple
of warnings by explicitly adding a couple of fallthrough pseudo-keywords
instead of letting the code fall through to the next case.

Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
Changes in v2:
  Make use of a break statement instead of fallthrough for consistency.
  Link: https://lore.kernel.org/lkml/20201123093347.719a77cf@xps13/

  drivers/mtd/nand/raw/stm32_fmc2_nand.c | 2 ++
  1 file changed, 2 insertions(+)

diff --git a/drivers/mtd/nand/raw/stm32_fmc2_nand.c b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
index 550bda4d1415..1c277fbb91f2 100644
--- a/drivers/mtd/nand/raw/stm32_fmc2_nand.c
+++ b/drivers/mtd/nand/raw/stm32_fmc2_nand.c

@@ -531,6 +531,7 @@ static int stm32_fmc2_nfc_ham_correct(struct nand_chip *chip, u8 *dat,
  		switch (b % 4) {
  		case 2:
  			bit_position += shifting;
+			break;
  		case 1:
  			break;
  		default:

@@ -546,6 +547,7 @@ static int stm32_fmc2_nfc_ham_correct(struct nand_chip *chip, u8 *dat,
  		switch (b % 4) {
  		case 2:
  			byte_addr += shifting;
+			break;
  		case 1:
  			break;
  		default: