ISH: added sleep mask for UART port
ISH: added sleep mask for UART port

added UART sleep mask not to allow to enter into deep sleep.

BUG=None
BRANCH=master
Test='make -j buildall'

Change-Id: I15e55c2c94276da99339465f2ea577b1f94e1ce4
Signed-off-by: Kyoung Kim <0fa79f8568f83616b048a28252e7d9ad3c59c80d@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/644848
Commit-Ready: Kyoung Il Kim <0fa79f8568f83616b048a28252e7d9ad3c59c80d@intel.com>
Tested-by: Kyoung Il Kim <0fa79f8568f83616b048a28252e7d9ad3c59c80d@intel.com>
Reviewed-by: Aaron Durbin <af0622ab041e8b0f8e5819838dcc93898196e71f@chromium.org>

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