common/keyboard_8042: Update kblog while holding mutex
common/keyboard_8042: Update kblog while holding mutex

i8042_send_to_host can be called from multiple tasks. Make sure we don't
mix up or lose any kblog entries.

BUG=b:145575366
BRANCH=none
TEST=Built and saw kblog is still populated.

Signed-off-by: Raul E Rangel <9a9c998e11a2655b1de9a05eeeef5f710c0dc7ed@chromium.org>
Change-Id: I5d036f6db4c829c2071850c1ec92f74a24b135b7
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2079692
Reviewed-by: Edward Hill <db1406b34e091703092b6b136bdfeb2c8125fc0e@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec