dcmihandler: update data_len to zero when getPowerReading command failed

Issue: heap data is leaked by sending the getPowerReading command

Fix: set the data_len to zero in getPowerReading command so that data is
not leaked when error occurred during getPowerReading.

Tested:

Command: FS1:\cmdtool\> cmdtool.efi 20 B0 02 DC 2c 2d 2f
Response: FF DC

Command: FS1:\cmdtool\> cmdtool.efi 20 B0 02 DC 2c 2d 2f 02 0d DC
Response: FF DC

Signed-off-by: Chalapathi Venkataramashetty <chalapathix.venkataramashetty@intel.com>
Change-Id: I33657439ffd5a632856382715e22377e18258826
1 file changed