ARM: mach-shmobile: r8a7740: cleanup I2C workaround method

Current workaround of I2C on r8a7740 used mdelay(),
but it was an overkill.
This patch cleans up the workaround delay.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Simon Horman <horms@verge.net.au>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

arch/arm/mach-shmobile/setup-r8a7740.c

@@ -350,19 +350,19 @@ static void r8a7740_i2c_workaround(struct platform_device *pdev)
 	i2c_write(reg, ICSTART, i2c_read(reg, ICSTART) | 0x10);
 	i2c_read(reg, ICSTART); /* dummy read */
 
-	mdelay(100);
+	udelay(10);
 
 	i2c_write(reg, ICCR, 0x01);
-	i2c_read(reg, ICCR);
 	i2c_write(reg, ICSTART, 0x00);
-	i2c_read(reg, ICSTART);
+
+	udelay(10);
 
 	i2c_write(reg, ICCR, 0x10);
-	mdelay(100);
+	udelay(10);
 	i2c_write(reg, ICCR, 0x00);
-	mdelay(100);
+	udelay(10);
 	i2c_write(reg, ICCR, 0x10);
-	mdelay(100);
+	udelay(10);
 
 	iounmap(reg);
 }