i2c: Fix error value returned by several bus drivers

When adding checks for ACPI resource conflicts to many bus drivers,
not enough attention was paid to the error paths, and for several
drivers this causes 0 to be returned on error in some cases. Fix this
by properly returning a non-zero value on every error.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: stable@kernel.org
diff --git a/drivers/i2c/busses/i2c-sis5595.c b/drivers/i2c/busses/i2c-sis5595.c
index 4375866..6d60284 100644
--- a/drivers/i2c/busses/i2c-sis5595.c
+++ b/drivers/i2c/busses/i2c-sis5595.c
@@ -147,7 +147,7 @@
 	u16 a;
 	u8 val;
 	int *i;
-	int retval = -ENODEV;
+	int retval;
 
 	/* Look for imposters */
 	for (i = blacklist; *i != 0; i++) {
@@ -223,7 +223,7 @@
 
 error:
 	release_region(sis5595_base + SMB_INDEX, 2);
-	return retval;
+	return -ENODEV;
 }
 
 static int sis5595_transaction(struct i2c_adapter *adap)