mtd, nand: move some printfs to debug output.

mtd, nand: move some printfs to debug output.

current U-Boot shows on startup (for example on the enbw_cmc
board) the following printfs from the nand subsystem:

Flash: 2 MiB
NAND:  Bad block table found at page 65472, version 0x01
Bad block table found at page 65408, version 0x01
nand_read_bbt: Bad block at 0x000002980000
nand_read_bbt: Bad block at 0x000003240000
128 MiB
MMC:   davinci: 0

remove them to debug output, so it shows with this patch:

Flash: 2 MiB
NAND:  128 MiB
MMC:   davinci: 0

Signed-off-by: Heiko Schocher <hs@denx.de>
Cc: Scott Wood <scottwood@freescale.com>
Signed-off-by: Scott Wood <scott@tyr.buserror.net>