chip/mt8192_scp: add missing guard for TASK_HOSTCMD
chip/mt8192_scp: add missing guard for TASK_HOSTCMD

BRANCH=none
BUG=b:160382789
BUG=b:163459890
TEST=1. remove hostcmd task from ec.tasklist
     2. make BOARD=asurada_scp

Signed-off-by: Tzung-Bi Shih <5e6f7578cd434ae5b4c9ffe5250f7a87a25045d7@chromium.org>
Change-Id: Ia92abeccd5fba8862563a200cbdcf4ce461f4106
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2351639
Reviewed-by: Ting Shen <c671d3efec3d7e7e285f3788bf0d1ba4c8605b78@chromium.org>

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