ec/quanta/it8518: correct ACPI battery data fed into ToString()

ToString() requires the input buffer data to be null-terminated,
but the data returned by the EC is not, leading Windows to fail
to report any battery data at all.  Correct this by concatenating
a null terminator (0x00) to the end of the buffer data before
inputting to ToString() where needed

TEST: boot Windows on google/stout, observe battery data
reported correctly.

Change-Id: I974afcd6ff1c617301d0897d6bd1fe14200aa3b9
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/21579
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
1 file changed