slim_ngd: Avoid unnecessary pipe connect/disconnect for msg queues

If slimbus satellite device retains its logical address after power
vote, it is safe to assume that BAM HW did not get reinitialized.
Use that logic to disconnect TX/RX message queues to avoid
disconnecting and reconnecting them during every power up/down vote

Change-Id: I906c4f5f01ed076066a084a8aa10d8e4d4825e33
Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>