IOCTL: Do not access register when device is disabled in reset

DEVICE_RESET is allowed even when device is in disabled state. However,
there is an option for DEVICE_RESET to access registers. We need to
disallow register accesses if device is disabled. Otherwise, it could
lead to ITMON errors.

Bug: 195731663
Test: GCA, CTS
Signed-off-by: Edmond Chung <edmondchung@google.com>
Change-Id: I11cb4973bd03b00a2cf1f6222097d4e959a40e09