msm: ipa: Fix to read all QMI responses from modem

Tethered stats will be polled every few seconds. In some
cases there will be a possibility that modem doesn't respond back
to the request on time and sends both the responses for the next
request. This can result in a stall where SYNC message is not read
by IPA QMI driver. Make a change to read all QMI responses from modem
instead of reading only once.

Change-Id: I312a38bac91c7feab2df3a2b35cb3c3c32624db4
Acked-by: Chaitanya Pratapa <cpratapa@qti.qualcomm.com>
Signed-off-by: Ravinder Konka <rkonka@codeaurora.org>