i2c: mlxcpld: Decrease polling time for performance improvement

Decrease polling time 'MLXCPLD_I2C_POLL_TIME' from 2000 usec to 400
usec. It greatly improves performance of I2C transactions.

Reliability of setting polling time to 400 usec has been thoroughly
validated across all the supported systems.
Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

drivers/i2c/busses/i2c-mlxcpld.c

@@ -25,7 +25,7 @@
 #define MLXCPLD_I2C_MAX_ADDR_LEN	4
 #define MLXCPLD_I2C_RETR_NUM		2
 #define MLXCPLD_I2C_XFER_TO		500000 /* usec */
-#define MLXCPLD_I2C_POLL_TIME		2000   /* usec */
+#define MLXCPLD_I2C_POLL_TIME		400   /* usec */
 
 /* LPC I2C registers */
 #define MLXCPLD_LPCI2C_CPBLTY_REG	0x0