Revert "I2C: OMAP: correct SYSC register offset for OMAP4"

This reverts commit 6c8e76e158a9bc849ec946ab030595e06ad89210.
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index dbed621..ead17f9 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -234,7 +234,7 @@
 	[OMAP_I2C_BUF_REG] = 0x94,
 	[OMAP_I2C_CNT_REG] = 0x98,
 	[OMAP_I2C_DATA_REG] = 0x9c,
-	[OMAP_I2C_SYSC_REG] = 0x10,
+	[OMAP_I2C_SYSC_REG] = 0x20,
 	[OMAP_I2C_CON_REG] = 0xa4,
 	[OMAP_I2C_OA_REG] = 0xa8,
 	[OMAP_I2C_SA_REG] = 0xac,