sb/intel/bd82x6x: Use PCI bitwise ops

Some cases could not be factored out while keeping reproducibility.
Also mark some potential bugs with a FIXME comment, since fixing them
while also keeping the binary unchanged is pretty much impossible.

Tested with BUILD_TIMELESS=1, Asus P8Z77-V LX2 does not change.

Change-Id: Iafe62d952a146bf53a28a1a83b87a3ae31f46720
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/42152
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
diff --git a/src/southbridge/intel/bd82x6x/smbus.c b/src/southbridge/intel/bd82x6x/smbus.c
index 1b72ea5..dcd2724 100644
--- a/src/southbridge/intel/bd82x6x/smbus.c
+++ b/src/southbridge/intel/bd82x6x/smbus.c
@@ -15,6 +15,7 @@
 	u16 reg16;
 
 	/* Enable clock gating */
+	/* FIXME: Using 32-bit ops with a 16-bit variable is a bug! These should be 16-bit! */
 	reg16 = pci_read_config32(dev, 0x80);
 	reg16 &= ~((1 << 8)|(1 << 10)|(1 << 12)|(1 << 14));
 	pci_write_config32(dev, 0x80, reg16);