CHROMIUM: arm64: qcom: mistral: Specify pinconf for SPI

Specify pinconf for the NOR related SPI lines, to avoid reported
electrical issues.

BUG=b:127191167
TEST=Validation of debugfs/gpio and ran flashrom -r

Change-Id: I945b487f7e53af0da7ff0eb815ed04648d38c5dd
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Mayank Chopra <mak.chopra@codeaurora.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/1601893


Reviewed-by: Zhihong Yu <zhihongyu@chromium.org>
Commit-Queue: Zhihong Yu <zhihongyu@chromium.org>
Tested-by: Zhihong Yu <zhihongyu@chromium.org>