diag: NRT read wakelocks held for very long time

During on-device logging with '-b' option,
NRT read wakelocks i.e. diag_nrt_modem_read
and diag_nrt_wcnss_read were held for more than
a day's time. This patch releases the wakelocks
even if SMD channel will be closed.

Change-Id: I7d211aaeaeb8d59369a191c5eef54c02a1b4a61d
CRs-Fixed: 513309
Signed-off-by: Mohit Aggarwal <maggarwa@codeaurora.org>