Allow ForEachVma*() APIs to use /proc/<pid>/maps

Not all clients are interested in the mem usage stats parsed
from smaps. Allow using ForEachVma*() methods with /proc/<pid>/maps.

Bug: 181174877
Test: libmeminfo_test
Change-Id: I032e0cbf5707a8c305e0d0a4e47013503465bad1
4 files changed