ap_pwrseq: Increase AP_PWRSEQ_STACK_SIZE
ap_pwrseq: Increase AP_PWRSEQ_STACK_SIZE

This is required to avoid stack overflow when triggering
system shutdown.

BUG=b:225756599
TEST=Boot SOC to OS; issue command 'shutdown -h now';
     System should power down to G3.
BRANCH=none

Signed-off-by: Perez Priego, Bernardo <3ff0f293f0ef5851019f0373e3bdce35ae659fd0@intel.com>
Change-Id: If7b67443b8d67ab1ff91e8b095cbcd4b28d3cabd
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3541339
Reviewed-by: Andrew McRae <44ad1424cfc8411c96d9181798ca41ae55709dfb@google.com>
Reviewed-by: Li1 Feng <0fd15d95d647a38d004d7ac9a3d0587bb1c98551@intel.com>
Commit-Queue: Andrew McRae <44ad1424cfc8411c96d9181798ca41ae55709dfb@google.com>

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