msm: ipa4: register only apps cons with PM

Register only APPS pipes with IPA PM instead of all system pipes.
Other pipes have their clients to register to IPA PM.

Change-Id: Iffcf21d04fbf6272ee6baf88644f70d1d49253b3
CRs-Fixed: 2202001
Acked-by: Ady Abraham <adya@qti.qualcomm.com>
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>