ueventd: replace ueventd_parser.cpp with init_parser.cpp

Previously init_parser.cpp was made generic and capable of parsing any
number of differently named 'sections' or prefixed lines.  We now use
these capabilities to do the parsing for ueventd.

Bug: 36250207
Bug: 33785894

Test: boot bullhead and ensure the right /dev nodes exist
      with the right permissions set
Test: verify no boot time difference
Change-Id: I698ca962d414f8135af32f6c9cd778841b2b8b53