ASoC: msm: Reset the stream open flag after CMD_CLOSE is sent to DSP

In case of gapless playback, driver does not wait for EOS. CMD_CLOSE
for stream one or two can be called from compress driver free before
EOS ACK for stream one is received. This can result in CMD_CLOSE to
be sent for already closed stream. Reset the stream open flag after
CMD_CLOSE is sent to DSP to prevent multiple CMD_CLOSE on same
stream.

Change-Id: Ic186ae37a760a2996ebd7b9b5dc5d5846621ab66
Signed-off-by: Krishnankutty Kolathappilly <kkolat@codeaurora.org>