Remove dependency on libprocessgroup.so

libprocessgroup.so was pulling in libcgrouprc.so
which added a requireNativeLib to our apex requiring
coverage for it.

libprocessgroup.so was only used to raise the priority
of a uipc task, which is a legacy way of the stack to send
audio and should be replaced by HIDL or AIDL.

Test: libcgrouprc is not part of requireNativeLibs in apex_manifest
Fix: 274006628
Fix: 274008074
Fix: 274008052
Fix: 274008062
Fix: 274006620
Fix: 274004991
Change-Id: I5f38bf4c80b29c3c603b59f641ec86cdac608204