cr50: increase console task stack size
cr50: increase console task stack size

The current console stack size prevents using it for even simpler TPM
library invocations. With this increase it is possible to invoke TPM
NV access API from console commands.

BRANCH=Cr50
BUG=b:62537474
TEST=with the rest of the patches verified that FWMP contents can be
     read from a console command.

     shmem console command output shows 6616 bytes of free SRAM space
     when in prod mode and 6624 bytes when in dev mode.

Change-Id: I177af1abde422dab0a9fdb0f4619eaf0ffefa9f6
Signed-off-by: Vadim Bendebury <5515d6d2d0829cbe0dd0dcf2094aaded06d58514@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/817895
Reviewed-by: Mary Ruthven <81380f3403fed74252e92df3ed012a1819ec6296@chromium.org>

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