Add datasheet links for the components supporting GPIO. This includes
I2C I/O ports, I2C PWMs, bus buffers and multiplexers.
TEST=None
Change-Id: I0a1d222d6f9bdbd824b78edf2338cd797e83ebba
Signed-off-by: Lee Leahy <leroy.p.leahy@intel.com>
Reviewed-on: https://review.coreboot.org/14114
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
b953d05e60
