init.rc: remove LMK (lowmemorykiller) entries

Those can be set in a script and in build.prop, no need to fiddle with
the init process.
The two sysfs files for controlling LMK are:
/sys/module/lowmemorykiller/parameters/minfree
/sys/module/lowmemorykiller/parameters/adj

Change-Id: I57f593ee2d1ac3853c3f2f652cdeaf01341771e6
Signed-off-by: Dan Trifan <jimsth@gmail.com>