usb: typec: tcpci_mt6360: remove unused mt6360_tcpc_read16 function

clang with W=1 reports
drivers/usb/typec/tcpm/tcpci_mt6360.c:46:19: error: unused function
  'mt6360_tcpc_read16' [-Werror,-Wunused-function]
static inline int mt6360_tcpc_read16(struct regmap *regmap,
                  ^
This function is not used, so remove it.
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230319141053.1703937-1-trix@redhat.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/tcpm/tcpci_mt6360.c

@@ -43,12 +43,6 @@ struct mt6360_tcpc_info {
 	int irq;
 };
 
-static inline int mt6360_tcpc_read16(struct regmap *regmap,
-				     unsigned int reg, u16 *val)
-{
-	return regmap_raw_read(regmap, reg, val, sizeof(u16));
-}
-
 static inline int mt6360_tcpc_write16(struct regmap *regmap,
 				      unsigned int reg, u16 val)
 {