mb/lenovo/{x200,t400}: Set SMBUS mux using common SB functions

Change-Id: I1e9a165b722006557557058a14e9f5dac78d4538
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/31189
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
diff --git a/src/mainboard/lenovo/t400/romstage.c b/src/mainboard/lenovo/t400/romstage.c
index 5020c85..44f560b 100644
--- a/src/mainboard/lenovo/t400/romstage.c
+++ b/src/mainboard/lenovo/t400/romstage.c
@@ -147,7 +147,7 @@
 	init_iommu();
 
 	/* FIXME: make a proper SMBUS mux support.  */
-	outl(inl(DEFAULT_GPIOBASE + 0x38) & ~0x400, DEFAULT_GPIOBASE + 0x38);
+	set_gpio(42, GPIO_LEVEL_LOW);
 
 	cbmem_initted = !cbmem_recovery(s3resume);
 
diff --git a/src/mainboard/lenovo/x200/romstage.c b/src/mainboard/lenovo/x200/romstage.c
index a0a1ace..c011356 100644
--- a/src/mainboard/lenovo/x200/romstage.c
+++ b/src/mainboard/lenovo/x200/romstage.c
@@ -118,7 +118,7 @@
 	init_iommu();
 
 	/* FIXME: make a proper SMBUS mux support.  */
-	outl(inl(DEFAULT_GPIOBASE + 0x38) & ~0x400, DEFAULT_GPIOBASE + 0x38);
+	set_gpio(42, GPIO_LEVEL_LOW);
 
 	cbmem_initted = !cbmem_recovery(s3resume);