mtd: nand: do not check R/B# for CMD_READID in nand_command(_lp)

Read ID (0x90) command does not toggle the R/B# pin.  Without this
patch, NAND_CMD_READID falls into the default: label, then R/B# is
checked by chip->dev_ready().

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

[ Linux commit: 3158fa0e739615769cc047d2428f30f4c3b6640e ]

drivers/mtd/nand/nand_base.c

@@ -651,6 +651,7 @@ static void nand_command(struct mtd_info *mtd, unsigned int command,
 	case NAND_CMD_ERASE2:
 	case NAND_CMD_SEQIN:
 	case NAND_CMD_STATUS:
+	case NAND_CMD_READID:
 		return;
 
 	case NAND_CMD_RESET:
@@ -748,6 +749,7 @@ static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
 	case NAND_CMD_SEQIN:
 	case NAND_CMD_RNDIN:
 	case NAND_CMD_STATUS:
+	case NAND_CMD_READID:
 		return;
 
 	case NAND_CMD_RESET: