i2c: at91: fix clk_offset for sam9x60

In SAM9X60 datasheet, FLEX_TWI_CWGR register description mentions clock
offset of 3 cycles (compared to 4 in eg. SAMA5D3).
This is the same offset as in SAMA5D2.

Fixes: b002779 ("i2c: at91: add new platform support for sam9x60")
Suggested-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Reviewed-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/i2c/busses/i2c-at91-core.c

@@ -174,7 +174,7 @@ static struct at91_twi_pdata sama5d2_config = {
 
 static struct at91_twi_pdata sam9x60_config = {
 	.clk_max_div = 7,
-	.clk_offset = 4,
+	.clk_offset = 3,
 	.has_unre_flag = true,
 	.has_alt_cmd = true,
 	.has_hold_field = true,