Ignore non-exec and /dev/ maps.

When caching elf maps, do not try and cache a map that is not readable
and writable or is in /dev/. The only exception is to allow caching
maps which begins with /dev/ashmem/.

Bug: 26589772
Change-Id: I670bc5869d125f48f72ee583156db1d4806ca7b9
1 file changed