nfc: fix typo

change 'regster' to 'register'

Signed-off-by: wengjianfeng <wengjianfeng@yulong.com>
Acked-by: Mark Greer <mgreer@animalcreek.com>
Link: https://lore.kernel.org/r/20210123082550.3748-1-samirweng1979@163.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/nfc/trf7970a.c

@@ -169,7 +169,7 @@
 
 /* Bits determining whether its a direct command or register R/W,
  * whether to use a continuous SPI transaction or not, and the actual
- * direct cmd opcode or regster address.
+ * direct cmd opcode or register address.
  */
 #define TRF7970A_CMD_BIT_CTRL			BIT(7)
 #define TRF7970A_CMD_BIT_RW			BIT(6)