soc/amd/stoneyridge/acpi: Create a GPIO library

There are some acpigen functionality that have not been implemented. In
order to implement them, ACPI GPIO functions to read and write to the
control MMIO of a particular pin is needed. So as a preliminary task to
implementing acpigen functions, create a library with functions to be
accessed by acpigen generated ACPI code.

BUG=b:79546790
TEST=Build grunt, more tests with commit 0f2acbd6b1.

Change-Id: I21c014b7f2698dd9193dae3113b18ee2a7303bcf
Signed-off-by: Richard Spiegel <richard.spiegel@silverbackltd.com>
Reviewed-on: https://review.coreboot.org/26334
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
3 files changed